Question

The committee should have all 4 professors and 1 research associate or all 3 trainees and 2 professors?

• A. 12
• B. 13
• C. 24
• D. 52
• E. None of these

Answer 1

The correct option is A 12

The committee of five members is to be formed that it has all 4 professors and search associates or all 3 trainees and 2 professors.
Therefore, number of combinations
${=}^4{C}_4{\times }^5{C}_1{+}^3{C}_3{\times }^4{C}_2=1\times 6+1\times 6$
= 12