Solution
Step 1: Create Table
| A | B | C | D | E | Required | |
|---|---|---|---|---|---|---|
| Sun | 3 | |||||
| Mon | 2 | |||||
| Tue | 2 | |||||
| Wed | 2 | |||||
| Thur | 2 | |||||
| Fri | 2 | |||||
| Sat | 2 | |||||
| Required | 3 | 3 | 3 | 3 | 3 |
Let the 5 employees be A, B, C, D and E.
Each employee works at least 3 days (2 days are consecutive, 3rd day is not consecutive)
We need 3 people working on Sunday, 2 on other days.
There is no one correct method to solve it. The order of solving can be different. Focus on finding the table-cells which can be ticked/crossed-off, hence, making a table (like above) is very helpful to visualise the problem!
Step 2: Populate information from Clue-2
| A | B | C | D | E | Required | |
|---|---|---|---|---|---|---|
| Sun | 3 | |||||
| Mon | 2 | |||||
| Tue | ☑ | . | . | ☑ | . | 2 |
| Wed | ☑ | . | . | ☑ | . | 2 |
| Thur | 2 | |||||
| Fri | 2 | |||||
| Sat | 2 | |||||
| Required | 3 | 3 | 3 | 3 | 3 |
Point 2: Alex and Dilip work together on Tuesday and Wednesday. Ergo, no one else can work on those days.
Step 3: Populate information from Clue-4
| A | B | C | D | E | Required | |
|---|---|---|---|---|---|---|
| Sun | ☑ | 3 | ||||
| Mon | . | 2 | ||||
| Tue | ☑ | . | . | ☑ | . | 2 |
| Wed | ☑ | . | . | ☑ | . | 2 |
| Thur | ☑ | 2 | ||||
| Fri | ☑ | 2 | ||||
| Sat | . | 2 | ||||
| Required | 3 | 3 | 3 | 3 | 3 |
Point 4: Cathy does not work either on Saturday or on Monday. Hence, she can work only on Sunday, Thursday and Friday.
Step 4: Can't work for 3 consecutive days
| A | B | C | D | E | Required | |
|---|---|---|---|---|---|---|
| Sun | . | ☑ | 3 | |||
| Mon | . | . | . | 2 | ||
| Tue | ☑ | . | . | ☑ | . | 2 |
| Wed | ☑ | . | . | ☑ | . | 2 |
| Thur | . | ☑ | . | 2 | ||
| Fri | . | ☑ | 2 | |||
| Sat | . | 2 | ||||
| Required | 3 | 3 | 3 | 3 | 3 |
Alex and Dilip can't work on Monday or Thursday, else, it'll violate the rule of 3 consecutive days.
Point 3: Cathy and Babha don't work with Alex on the same day. So, Alex won't work on the days Cathy works (Sunday, Thursday, Friday).
Step 5: Filling Alex's working days
| A | B | C | D | E | Required | |
|---|---|---|---|---|---|---|
| Sun | . | ☑ | 3 | |||
| Mon | . | . | . | 2 | ||
| Tue | ☑ | . | . | ☑ | . | 2 |
| Wed | ☑ | . | . | ☑ | . | 2 |
| Thur | . | ☑ | . | 2 | ||
| Fri | . | ☑ | 2 | |||
| Sat | ☑ | . | . | 2 | ||
| Required | 3 | 3 | 3 | 3 | 3 |
Hence, Alex has to work on Saturday to fulfil the 3 working days criteria.
Recall Point 3: Cathy and Babha don't work with Alex on the same day. So, Bhabha won't work on Satuday.
Step 6: Filling Monday
| A | B | C | D | E | Required | |
|---|---|---|---|---|---|---|
| Sun | . | ☑ | 3 | |||
| Mon | . | ☑ | . | . | ☑ | 2 |
| Tue | ☑ | . | . | ☑ | . | 2 |
| Wed | ☑ | . | . | ☑ | . | 2 |
| Thur | . | ☑ | . | 2 | ||
| Fri | . | ☑ | 2 | |||
| Sat | ☑ | . | . | 2 | ||
| Required | 3 | 3 | 3 | 3 | 3 |
We see that only Bhabha and Ethan are free on Monday (which requires 2 employees).
Step 7: Filling Saturday
| A | B | C | D | E | Required | |
|---|---|---|---|---|---|---|
| Sun | . | ☑ | 3 | |||
| Mon | . | ☑ | . | . | ☑ | 2 |
| Tue | ☑ | . | . | ☑ | . | 2 |
| Wed | ☑ | . | . | ☑ | . | 2 |
| Thur | . | ☑ | . | 2 | ||
| Fri | . | ☑ | 2 | |||
| Sat | ☑ | . | . | . | ☑ | 2 |
| Required | 3 | 3 | 3 | 3 | 3 |
Point 2: Alex and Dilip work together on Tuesday and Wednesday while the other working day differs for them.
Hence, Dilip will not work on Satuday (as Alex is working).
Thus, only Ethan can work on Satuday to fulfil Saturday's requirement.
Step 8: Filling Sunday
| A | B | C | D | E | Required | |
|---|---|---|---|---|---|---|
| Sun | . | ☑ | ☑ | ☑ | . | 3 |
| Mon | . | ☑ | . | . | ☑ | 2 |
| Tue | ☑ | . | . | ☑ | . | 2 |
| Wed | ☑ | . | . | ☑ | . | 2 |
| Thur | . | ☑ | . | 2 | ||
| Fri | . | ☑ | . | 2 | ||
| Sat | ☑ | . | . | . | ☑ | 2 |
| Required | 3 | 3 | 3 | 3 | 3 |
Ethan can't work on Sunday, else it'll become 3 consecutive days.
Hence, to fulfil the 3 employee requirement on Sunday, only Bhabha and Dilip can join Cathy.
Step 9: Filling Ethan
| A | B | C | D | E | Required | |
|---|---|---|---|---|---|---|
| Sun | . | ☑ | ☑ | ☑ | . | 3 |
| Mon | . | ☑ | . | . | ☑ | 2 |
| Tue | ☑ | . | . | ☑ | . | 2 |
| Wed | ☑ | . | . | ☑ | . | 2 |
| Thur | . | ☑ | . | . | 2 | |
| Fri | . | . | ☑ | . | ☑ | 2 |
| Sat | ☑ | . | . | . | ☑ | 2 |
| Required | 3 | 3 | 3 | 3 | 3 |
We need to have 2 consecutive days for Ethan -- only possible if he works on Friday. Thus, fulfilling his requirment and Friday's requirement.
Step 10: Filling Thursday
| A | B | C | D | E | Required | |
|---|---|---|---|---|---|---|
| Sun | . | ☑ | ☑ | ☑ | . | 3 |
| Mon | . | ☑ | . | . | ☑ | 2 |
| Tue | ☑ | . | . | ☑ | . | 2 |
| Wed | ☑ | . | . | ☑ | . | 2 |
| Thur | . | ☑ | ☑ | . | . | 2 |
| Fri | . | . | ☑ | . | ☑ | 2 |
| Sat | ☑ | . | . | . | ☑ | 2 |
| Required | 3 | 3 | 3 | 3 | 3 |
Finally, only Bhabha can work on Thursday and fulfil the remaining requirement.
Bhabha and Cathy work together on Sunday & Thursday (two times).