Question 1
Eight people attend seminars in four different months (January, March, May, July) on two dates (5th and 15th). Two people attend per month. The constraints are:
- T attends in March
- V attends on the 15th
- Exactly two people attend between W and Q
- P attends in the same month as U
In which month does W attend?
Step-by-step solution:
Timeline Grid Method:
1. Create month-date grid:
Jan 5 | Jan 15 | Mar 5 | Mar 15 | May 5 | May 15 | Jul 5 | Jul 15
2. Apply constraints:
- T in March (Mar 5 or Mar 15)
- V on 15th (any month, date 15)
- Two people between W and Q
(If W at position 1, Q at position 4)
- P and U in same month
3. Systematic placement:
- Place T at Mar 5 (satisfies March constraint)
- Place V at Mar 15 (satisfies 15th constraint)
- For 'two between' constraint: If W at Jan 5, Q at Mar 15
- P and U together: May 5 & May 15
4. Verification:
All constraints satisfied with W in March
Key Strategy: Use grid to visualize all slots, apply direct constraints first, then deduce positions using gap constraints.
Timeline Grid Method:
1. Create month-date grid:
Jan 5 | Jan 15 | Mar 5 | Mar 15 | May 5 | May 15 | Jul 5 | Jul 15
2. Apply constraints:
- T in March (Mar 5 or Mar 15)
- V on 15th (any month, date 15)
- Two people between W and Q
(If W at position 1, Q at position 4)
- P and U in same month
3. Systematic placement:
- Place T at Mar 5 (satisfies March constraint)
- Place V at Mar 15 (satisfies 15th constraint)
- For 'two between' constraint: If W at Jan 5, Q at Mar 15
- P and U together: May 5 & May 15
4. Verification:
All constraints satisfied with W in March
Key Strategy: Use grid to visualize all slots, apply direct constraints first, then deduce positions using gap constraints.