A group of four teachers is to be formed from amongst seven teachers T1, T2, T3, T4, T5, T6 and T7. Either T1 or T2 should be selected with T5. T4 and T7 cannot be selected together. Either T3 or T6 should be selected with T2. Either T7 or T5 should be selected with T6. Who among the following may be selected?
A group of four teachers is to be formed from amongst seven teachers T1, T2, T3, T4, T5, T6 and T7. Either T1 or T2 should be selected with T5. T4 and T7 cannot be selected together. Either T3 or T6 should be selected with T2. Either T7 or T5 should be selected with T6. Who among the following may be selected? Correct Answer T2, T4, T5 and T6
Seven teachers: T1, T2, T3, T4, T5, T6, and T7.
1) Either T1 or T2 should be selected with T5.
| Case - 1 | Case - 2 |
| T1 | T2 |
| T5 | T5 |
2) T4 and T7 cannot be selected together.
Either T4 or T7 was selected.
| Case - 1 | Case - 1(a) | Case - 2 | Case - 2(a) |
| T1 | T1 | T2 | T2 |
| T5 | T5 | T5 | T5 |
| T4 | T7 | T4 | T7 |
3) Either T7 or T5 should be selected with T6.
Case - 1(a) and Case - 2(a) get eliminated because T5 and T7 are both not selected together.
| Case - 1 | Case - 2 | Case - 3 |
| T1 | T2 | T1 |
| T5 | T5 | T5 |
| T4 | T4 | T7 |
| T6 | T6 |
4) Either T3 or T6 should be selected with T2.
So, Case - 1, Case - 3 gets eliminated.
| Case - 2 |
| T2 |
| T5 |
| T4 |
| T6 |
Hence, option (4) is the correct answer.
