Multi-Layer Puzzles - Beginner-Intermediate Level: systematic puzzles BEGINNER-INTERMEDIATE

Intensive quick response training 🎯 drill: 20 beginner-intermediate-level multi-layer puzzles questions. Worksheet 10 of 30 hones your systematic puzzles abilities. Practice complex arrangements, multiple constraints, combined conditions under timed conditions. Best for developing students seeking building on fundamentals with moderate challenges.

📝 Worksheet 10 of 30 • 20 questions • ⏱️ Estimated time: 20 minutes • 🎯 Beginner-intermediate level

What you'll learn in this worksheet:
Your progress through Multi-Layer Puzzles
Worksheet 10 of 30 (33% complete)

Question 1

Three project teams are working on multiple projects across four phases and four months. Each phase must be completed before the next begins. Given information: • Project Alpha: Planning phase by Team 1 in January, Development by Team 1 in February • Project Alpha: Testing phase in March, Deployment in April • Team 2 handles Testing and Deployment phases of Project Alpha • Project Beta: Planning in January by Team 2, Development in February • Team 3 handles Development and Testing of Project Beta • Project Beta Deployment is in April by Team 1 Which team handles the Testing phase of Project Beta?
Step-by-step Solution:

Layer 1: Project-Phase Matrix
Four phases for each project must occur sequentially.

Layer 2: Team Assignment

Project Alpha Timeline:
- Planning: Team 1 (January)
- Development: Team 1 (February)
- Testing: Team 2 (March)
- Deployment: Team 2 (April)

Project Beta Timeline:
- Planning: Team 2 (January)
- Development: Team 3 (February)
- Testing: Team 3 (March)
- Deployment: Team 1 (April)

Layer 3: Temporal Sequencing
Each project follows strict phase order: Planning → Development → Testing → Deployment

Cross-Layer Integration:
Project Beta Testing phase is handled by Team 3 (given in clues that Team 3 handles both Development and Testing of Project Beta).

Answer: Team 3

Question 2

Five security guards work in rotating shifts across three days. Each guard works one shift per day, and each shift has exactly one guard. Given information: • On Monday: Neha works Morning, Meera works Afternoon, Ajay works Evening • Each person's shift rotates one position forward each day (Morning → Afternoon → Evening → Night → Graveyard → Morning) • Sunil worked Night on Monday • Karan worked Graveyard on Monday What shift does Ajay work on Tuesday?
Step-by-step Solution:

Layer 1: Day-wise Schedule
Creating a temporal matrix across three days.

Layer 2: Shift Assignment
Initial assignments on Monday:
- Neha → Morning
- Meera → Afternoon
- Ajay → Evening
- Sunil → Night
- Karan → Graveyard

Layer 3: Rotation Pattern
Each person's shift advances by one position daily.

Day 2 (Tuesday) Calculation:
Ajay started with Evening on Monday.
After one rotation: Evening → Night

Answer: Night

Question 3

Six people live in three different buildings (Tower A, B, C). Each building has 2 floors. Each person has a different profession. Given information: • The Lawyer lives immediately above Rajesh (Tower B, F1) • The Doctor lives on Floor 1 of Tower A. • Karan and Sneha live in the same building (Tower C), and neither is the Engineer. • Priya lives in Tower B, but is not the Architect. • Neha lives on Floor 2 of Tower A. What is Neha's profession?
Step-by-step Solution (Requires 3 Parallel Layering Grids):

1. Establish Building and Floor Positions (Clue 1 & 5):
- Clue 5: Neha is in Tower A, F2.
- Clue 1: Priya (The Lawyer) is in Tower B, F2, immediately above Rajesh in Tower B, F1.

2. Departmental Grouping (Clue 3):
- Karan and Sneha are in Tower C.
- By elimination, the remaining person is Amit, who must be in Tower A.

3. Profession Mapping (Clue 2 & 3):
- Clue 2: Amit (Tower A, F1) is the Doctor.
- Clue 3: Karan and Sneha (Tower C) are NOT the Engineer.
- Deduction: Since Neha is in Tower A (and is not Doctor), and is the only person left in Tower A, Neha must be the Engineer.

Answer: Engineer

Question 4

Six items are placed on six shelves (1=bottom, 6=top). Each item has a unique color and is Small, Medium, or Large (exactly two of each). No two adjacent shelves have the same size. Items: Book, Vase, Clock, Frame, Lamp, Trophy Colors: Red, Blue, Green, Yellow, Black, White Given information: • The item on Shelf 6 is Medium-sized. No two adjacent shelves have the same size. • The item on Shelf 3 is Yellow colored. • The Red item is on Shelf 2, which is 3 shelves below the Trophy. • The Large-sized item is the Book. • The item on Shelf 1 is not Black. What item is on Shelf 4?
Step-by-step Solution:

1. Size Pattern (Clue 1):
- Shelf 6: Medium
- No adjacent same size + exactly 2 each → sizes forced:
- S6: Medium
- S5: Small
- S4: Large
- S3: Medium
- S2: Large
- S1: Small

2. Positional Relationship (Clue 3):
- The Red item is on Shelf 2
- Shelf 2 is 3 shelves below Shelf 5
- Therefore, Shelf 5 has the Trophy item

3. Size-Item Link (Clue 4):
- The Large-sized item is the Book
- Shelf 4 is Large-sized
- Therefore, Shelf 4 contains the Book

Complete Arrangement:

| Shelf | Item | Color | Size |
|-------|------|-------|------|
| 6 | Clock | Green | Medium |
| 5 | Trophy | White | Small |
| 4 | Lamp | Black | Large |
| 3 | Frame | Yellow | Medium |
| 2 | Book | Red | Large |
| 1 | Vase | Blue | Small |

Answer: Lamp

Question 5

Five runners are racing on three parallel tracks. Multiple runners can use the same track, and each runner's position is tracked within their track. Given information: • Alice and Diana are on Track 1 • Bob and Ethan are on Track 2 • Charlie is alone on Track 3 • On Track 1: Alice is ahead of Diana • On Track 2: Bob is ahead of Ethan • The person on Track 3 is running unopposed What is Diana's position within their track?
Step-by-step Solution:

Layer 1: Track Assignment (Horizontal Layer)
- Track 1: Alice, Diana
- Track 2: Bob, Ethan
- Track 3: Charlie

Layer 2: Position within Track (Competitive Layer)

Track 1 Rankings:
- Alice is ahead of Diana
- Therefore: Alice = 1st, Diana = 2nd

Track 2 Rankings:
- Bob is ahead of Ethan
- Therefore: Bob = 1st, Ethan = 2nd

Track 3 Rankings:
- Charlie = 1st (unopposed)

Cross-Track Analysis:
Diana is on Track 1 and is behind Alice.
Within Track 1, Diana is in 2nd position.

Answer: 2nd

Question 6

Six people work in three departments with two shift timings across three working days. Each person may work multiple days but only one shift per day. Given information: • **If** a person works the **Evening** shift, **then** they must be in the **HR** department. • Neha works Evening (Evening) shift in Marketing (Marketing) on Wednesday. • No person works Morning (Morning) shift on Friday (Friday) in the Marketing department. • Priya works in HR on Wednesday. If Rohan works in Sales and is on the Evening shift, which department must be the exception to the main conditional rule?
Step-by-step Solution (Requires Rule Exception Analysis):

1. Analyze the Core Conditional Rule (Clue 1):
- Rule: If Shift = Evening, then Department = HR.
- This implies: Any non-HR department cannot have an Evening shift worker.

2. Check the Contradictory Clue (Clue 2):
- Clue 2: Neha (a person) works Evening shift in the Marketing (Marketing) department.

3. Identify the Exception:
- Clue 2 presents a direct contradiction to Clue 1. Since all clues are given as true, the conditional rule must have an unstated exception.
- The person in the Marketing department works the Evening shift, violating the rule that all Evening shifters must be in HR.
- Therefore, Marketing is the implied exception to the Conditional Rule's outcome.

Answer: Marketing

Question 7

Six people live in three different buildings (Tower A, B, C). Each building has 2 floors. Each person has a different profession. Given information: • The Lawyer lives immediately above Rajesh (Tower B, F1) • The Doctor lives on Floor 1 of Tower A. • Karan and Sneha live in the same building (Tower C), and neither is the Engineer. • Priya lives in Tower B, but is not the Architect. • Neha lives on Floor 2 of Tower A. What is Neha's profession?
Step-by-step Solution (Requires 3 Parallel Layering Grids):

1. Establish Building and Floor Positions (Clue 1 & 5):
- Clue 5: Neha is in Tower A, F2.
- Clue 1: Priya (The Lawyer) is in Tower B, F2, immediately above Rajesh in Tower B, F1.

2. Departmental Grouping (Clue 3):
- Karan and Sneha are in Tower C.
- By elimination, the remaining person is Amit, who must be in Tower A.

3. Profession Mapping (Clue 2 & 3):
- Clue 2: Amit (Tower A, F1) is the Doctor.
- Clue 3: Karan and Sneha (Tower C) are NOT the Engineer.
- Deduction: Since Neha is in Tower A (and is not Doctor), and is the only person left in Tower A, Neha must be the Engineer.

Answer: Engineer

Question 8

Five individuals must be matched to their Car, Pet, and City of residence. No two individuals share any of these attributes. Given information: • **Either** the person with the **Bird** lives in **Chicago**, **OR** the person with the **Dog** drives a **Sedan**. • The person in **Boston** does not own a **Cat** and does not drive a **SUV**. • If a person drives a **Hatchback**, their city is not **NY**. • **Carl** is the one who owns the **Cat**. • The person who drives a **Truck** is **Evan**, who is also the one from **LA**. If you assume the second part of the Bi-Conditional clue (Clue 1) is **true**, what car does Alex drive?
Step-by-step Solution (Requires Case-Based Reasoning):

1. Analyze the Bi-Conditional Clue (Clue 1):
- Clue 1: (Pet=Bird → City=Chicago) OR (Pet=Dog → Car=Sedan)
- The question asks you to assume the second part is TRUE: The person with the Dog drives a Sedan.

2. Case 2 Deduction (Second part TRUE):
- Person X → Pet: Dog and Car: Sedan

3. Anchor Assignments (Clues 4 & 5):
- Clue 4: Carl → Pet: Cat.
- Clue 5: Evan → Car: Truck and City: LA.

4. Inter-Layer Elimination:
- Use the Exclusionary Clue 2 (Boston city) and Conditional Link Clue 3 (Hatchback car is not NY city).
- By tracking all exclusions and the definite assignments from the two layers, you can uniquely place the remaining Person, Car, Pet, and City for Alex.
- The only remaining car for Alex after all other constraints are met is the Hatchback.

Answer: Hatchback

Question 9

Six people work in two companies. Each company has multiple departments, and each department has multiple teams. Given information: • TechCorp has two departments: Engineering and Sales • InnoSoft has two departments: Marketing and HR • Engineering has Team Alpha and Team Beta • Sales has only Team Gamma • Marketing has only Team Delta • HR has Team Epsilon and Team Zeta • Anil is in Team Alpha, Bina is in Team Beta • Chirag works in Sales department of TechCorp • Divya is in Marketing department of InnoSoft • Esha and Farhan are in HR department, in different teams In which company does Esha work?
Step-by-step Solution:

Layer 1: Company Structure
Two companies: TechCorp, InnoSoft

Layer 2: Department within Company

TechCorp Departments:
- Engineering
- Sales

InnoSoft Departments:
- Marketing
- HR

Layer 3: Teams within Departments

TechCorp → Engineering:
- Team Alpha
- Team Beta

TechCorp → Sales:
- Team Gamma

InnoSoft → Marketing:
- Team Delta

InnoSoft → HR:
- Team Epsilon
- Team Zeta

Layer 4: Individual Assignment

TechCorp:
- Engineering → Team Alpha → Anil
- Engineering → Team Beta → Bina
- Sales → Team Gamma → Chirag

InnoSoft:
- Marketing → Team Delta → Divya
- HR → (HR teams) → Esha, Farhan

Nested Integration:
Esha is in HR department.
HR department exists only in InnoSoft.
Therefore, Esha works in InnoSoft.

Answer: InnoSoft

Question 10

Six people work in two companies. Each company has multiple departments, and each department has multiple teams. Given information: • TechCorp has two departments: Engineering and Sales • InnoSoft has two departments: Marketing and HR • Engineering has Team Alpha and Team Beta • Sales has only Team Gamma • Marketing has only Team Delta • HR has Team Epsilon and Team Zeta • Anil is in Team Alpha, Bina is in Team Beta • Chirag works in Sales department of TechCorp • Divya is in Marketing department of InnoSoft • Esha and Farhan are in HR department, in different teams In which company does Esha work?
Step-by-step Solution:

Layer 1: Company Structure
Two companies: TechCorp, InnoSoft

Layer 2: Department within Company

TechCorp Departments:
- Engineering
- Sales

InnoSoft Departments:
- Marketing
- HR

Layer 3: Teams within Departments

TechCorp → Engineering:
- Team Alpha
- Team Beta

TechCorp → Sales:
- Team Gamma

InnoSoft → Marketing:
- Team Delta

InnoSoft → HR:
- Team Epsilon
- Team Zeta

Layer 4: Individual Assignment

TechCorp:
- Engineering → Team Alpha → Anil
- Engineering → Team Beta → Bina
- Sales → Team Gamma → Chirag

InnoSoft:
- Marketing → Team Delta → Divya
- HR → (HR teams) → Esha, Farhan

Nested Integration:
Esha is in HR department.
HR department exists only in InnoSoft.
Therefore, Esha works in InnoSoft.

Answer: InnoSoft

Question 11

Six people live in three different buildings (Tower A, B, C). Each building has 2 floors. Each person has a different profession. Given information: • The Lawyer lives immediately above Rajesh (Tower B, F1) • The Doctor lives on Floor 1 of Tower A. • Karan and Sneha live in the same building (Tower C), and neither is the Engineer. • Priya lives in Tower B, but is not the Architect. • Neha lives on Floor 2 of Tower A. What is Neha's profession?
Step-by-step Solution (Requires 3 Parallel Layering Grids):

1. Establish Building and Floor Positions (Clue 1 & 5):
- Clue 5: Neha is in Tower A, F2.
- Clue 1: Priya (The Lawyer) is in Tower B, F2, immediately above Rajesh in Tower B, F1.

2. Departmental Grouping (Clue 3):
- Karan and Sneha are in Tower C.
- By elimination, the remaining person is Amit, who must be in Tower A.

3. Profession Mapping (Clue 2 & 3):
- Clue 2: Amit (Tower A, F1) is the Doctor.
- Clue 3: Karan and Sneha (Tower C) are NOT the Engineer.
- Deduction: Since Neha is in Tower A (and is not Doctor), and is the only person left in Tower A, Neha must be the Engineer.

Answer: Engineer

Question 12

Five boxes (A, B, C, D, E) are stacked vertically (Position 1 is bottom, 5 is top). Each box is painted a different color from: Yellow, Green, Blue, Red, White. Given information: • Box A is at the bottom (Position 1). • The White box is at the top (Position 5). • Box C is immediately above Box B. • The box at Position 3 is Blue. • Box C is not Red. What color is Box D?
Step-by-step Solution:

1. Direct Placements:
- Position 1: Box A (Yellow)
- Position 5: Box E (White)
- Position 3: Blue

2. Build Complete Stack:

| Position | Box | Color |
|----------|-----|-------|
| 5 | E | White |
| 4 | D | Red |
| 3 | C | Blue |
| 2 | B | Green |
| 1 | A | Yellow |

3. Find Box D:
- Box D is at Position 4
- Its color is Red

Answer: Red

Question 13

Six people work in three departments with two shift timings across three working days. Each person may work multiple days but only one shift per day. Given information: • **If** a person works the **Evening** shift, **then** they must be in the **HR** department. • Neha works Evening (Evening) shift in Marketing (Marketing) on Wednesday. • No person works Morning (Morning) shift on Friday (Friday) in the Marketing department. • Priya works in HR on Wednesday. If Rohan works in Sales and is on the Evening shift, which department must be the exception to the main conditional rule?
Step-by-step Solution (Requires Rule Exception Analysis):

1. Analyze the Core Conditional Rule (Clue 1):
- Rule: If Shift = Evening, then Department = HR.
- This implies: Any non-HR department cannot have an Evening shift worker.

2. Check the Contradictory Clue (Clue 2):
- Clue 2: Neha (a person) works Evening shift in the Marketing (Marketing) department.

3. Identify the Exception:
- Clue 2 presents a direct contradiction to Clue 1. Since all clues are given as true, the conditional rule must have an unstated exception.
- The person in the Marketing department works the Evening shift, violating the rule that all Evening shifters must be in HR.
- Therefore, Marketing is the implied exception to the Conditional Rule's outcome.

Answer: Marketing

Question 14

Six people work in three departments with two shift timings across three working days. Each person may work multiple days but only one shift per day. Given information: • **If** a person works the **Evening** shift, **then** they must be in the **HR** department. • Neha works Evening (Evening) shift in Marketing (Marketing) on Wednesday. • No person works Morning (Morning) shift on Friday (Friday) in the Marketing department. • Priya works in HR on Wednesday. If Rohan works in Sales and is on the Evening shift, which department must be the exception to the main conditional rule?
Step-by-step Solution (Requires Rule Exception Analysis):

1. Analyze the Core Conditional Rule (Clue 1):
- Rule: If Shift = Evening, then Department = HR.
- This implies: Any non-HR department cannot have an Evening shift worker.

2. Check the Contradictory Clue (Clue 2):
- Clue 2: Neha (a person) works Evening shift in the Marketing (Marketing) department.

3. Identify the Exception:
- Clue 2 presents a direct contradiction to Clue 1. Since all clues are given as true, the conditional rule must have an unstated exception.
- The person in the Marketing department works the Evening shift, violating the rule that all Evening shifters must be in HR.
- Therefore, Marketing is the implied exception to the Conditional Rule's outcome.

Answer: Marketing

Question 15

Six items are placed on six shelves (1=bottom, 6=top). Each item has a unique color and is Small, Medium, or Large (exactly two of each). No two adjacent shelves have the same size. Items: Book, Vase, Clock, Frame, Lamp, Trophy Colors: Red, Blue, Green, Yellow, Black, White Given information: • The item on Shelf 6 is Large-sized. No two adjacent shelves have the same size. • The item on Shelf 3 is Red colored. • The Green item is on Shelf 2, which is 3 shelves below the Lamp. • The Large-sized item is the Frame. • The item on Shelf 1 is not Red. What item is on Shelf 4?
Step-by-step Solution:

1. Size Pattern (Clue 1):
- Shelf 6: Large
- No adjacent same size + exactly 2 each → sizes forced:
- S6: Large
- S5: Small
- S4: Large
- S3: Medium
- S2: Small
- S1: Medium

2. Positional Relationship (Clue 3):
- The Green item is on Shelf 2
- Shelf 2 is 3 shelves below Shelf 5
- Therefore, Shelf 5 has the Lamp item

3. Size-Item Link (Clue 4):
- The Large-sized item is the Frame
- Shelf 4 is Large-sized
- Therefore, Shelf 4 contains the Frame

Complete Arrangement:

| Shelf | Item | Color | Size |
|-------|------|-------|------|
| 6 | Vase | Blue | Large |
| 5 | Lamp | Black | Small |
| 4 | Frame | Yellow | Large |
| 3 | Book | Red | Medium |
| 2 | Clock | Green | Small |
| 1 | Trophy | White | Medium |

Answer: Frame

Question 16

Six items are placed on six shelves (1=bottom, 6=top). Each item has a unique color and is Small, Medium, or Large (exactly two of each). No two adjacent shelves have the same size. Items: Book, Vase, Clock, Frame, Lamp, Trophy Colors: Red, Blue, Green, Yellow, Black, White Given information: • The item on Shelf 6 is Large-sized. No two adjacent shelves have the same size. • The item on Shelf 3 is Yellow colored. • The Green item is on Shelf 2, which is 3 shelves below the Trophy. • The Medium-sized item is the Book. • The item on Shelf 1 is not Yellow. What item is on Shelf 4?
Step-by-step Solution:

1. Size Pattern (Clue 1):
- Shelf 6: Large
- No adjacent same size + exactly 2 each → sizes forced:
- S6: Large
- S5: Small
- S4: Medium
- S3: Small
- S2: Large
- S1: Medium

2. Positional Relationship (Clue 3):
- The Green item is on Shelf 2
- Shelf 2 is 3 shelves below Shelf 5
- Therefore, Shelf 5 has the Trophy item

3. Size-Item Link (Clue 4):
- The Medium-sized item is the Book
- Shelf 4 is Medium-sized
- Therefore, Shelf 4 contains the Book

Complete Arrangement:

| Shelf | Item | Color | Size |
|-------|------|-------|------|
| 6 | Vase | Blue | Large |
| 5 | Trophy | White | Small |
| 4 | Lamp | Black | Medium |
| 3 | Frame | Yellow | Small |
| 2 | Clock | Green | Large |
| 1 | Book | Red | Medium |

Answer: Lamp

Question 17

Six people live in three different buildings (Tower A, B, C). Each building has 2 floors. Each person has a different profession. Given information: • The Lawyer lives immediately above Rajesh (Tower B, F1) • The Doctor lives on Floor 1 of Tower A. • Karan and Sneha live in the same building (Tower C), and neither is the Engineer. • Priya lives in Tower B, but is not the Architect. • Neha lives on Floor 2 of Tower A. What is Neha's profession?
Step-by-step Solution (Requires 3 Parallel Layering Grids):

1. Establish Building and Floor Positions (Clue 1 & 5):
- Clue 5: Neha is in Tower A, F2.
- Clue 1: Priya (The Lawyer) is in Tower B, F2, immediately above Rajesh in Tower B, F1.

2. Departmental Grouping (Clue 3):
- Karan and Sneha are in Tower C.
- By elimination, the remaining person is Amit, who must be in Tower A.

3. Profession Mapping (Clue 2 & 3):
- Clue 2: Amit (Tower A, F1) is the Doctor.
- Clue 3: Karan and Sneha (Tower C) are NOT the Engineer.
- Deduction: Since Neha is in Tower A (and is not Doctor), and is the only person left in Tower A, Neha must be the Engineer.

Answer: Engineer

Question 18

Five boxes (A, B, C, D, E) are stacked vertically (Position 1 is bottom, 5 is top). Each box is painted a different color from: White, Green, Blue, Red, Yellow. Given information: • Box A is at the bottom (Position 1). • The Yellow box is at the top (Position 5). • Box C is immediately above Box B. • The box at Position 3 is Blue. • Box B is not Blue. What color is Box C?
Step-by-step Solution:

1. Direct Placements:
- Position 1: Box A (White)
- Position 5: Box E (Yellow)
- Position 3: Blue

2. Build Complete Stack:

| Position | Box | Color |
|----------|-----|-------|
| 5 | E | Yellow |
| 4 | D | Red |
| 3 | C | Blue |
| 2 | B | Green |
| 1 | A | White |

3. Find Box C:
- Box C is at Position 3
- Its color is Blue

Answer: Blue

Question 19

Five boxes (A, B, C, D, E) are stacked vertically (Position 1 is bottom, 5 is top). Each box is painted a different color from: Blue, Yellow, Green, White, Red. Given information: • Box A is at the bottom (Position 1). • The Red box is at the top (Position 5). • Box C is immediately above Box B. • The box at Position 3 is Green. • Box C is not Red. What color is Box B?
Step-by-step Solution:

1. Direct Placements:
- Position 1: Box A (Blue)
- Position 5: Box E (Red)
- Position 3: Green

2. Build Complete Stack:

| Position | Box | Color |
|----------|-----|-------|
| 5 | E | Red |
| 4 | D | White |
| 3 | C | Green |
| 2 | B | Yellow |
| 1 | A | Blue |

3. Find Box B:
- Box B is at Position 2
- Its color is Yellow

Answer: Yellow

Question 20

Four people move between four zones (A, B, C, D) during three time slots. Each person is in exactly one zone at any time, and multiple people can be in the same zone. Given information: • At 9 AM: Ankit is in Zone A, Bindu is in Zone B, Chirag is in Zone C, Disha is in Zone D • Ankit moves: Zone A → Zone B → Zone C • Bindu moves: Zone B → stays in Zone B → Zone D • Chirag moves: Zone C → Zone D → Zone A • Disha moves: Zone D → stays in Zone D → Zone B Which zone has exactly two people at 10 AM?
Step-by-step Solution:

At 9 AM (9 AM):
- Ankit → Zone A
- Bindu → Zone B
- Chirag → Zone C
- Disha → Zone D

Movement to 10 AM (10 AM):
- Ankit moves from Zone A to Zone B
- Bindu stays in Zone B
- Chirag moves from Zone C to Zone D
- Disha stays in Zone D

At 10 AM (10 AM):
- Ankit → Zone B
- Bindu → Zone B
- Chirag → Zone D
- Disha → Zone D

Zone Occupancy:
- Zone A: 0 person
- Zone B: 2 people
- Zone C: 0 person
- Zone D: 2 people

Therefore, Zone B has exactly two people at 10 AM.
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