CA Foundation · Quantitative Aptitude · Permutations and Combinations
A Chennai firm has 7 chartered accountants and 5 company secretaries. A team of 4 members with exactly 2 chartered accountants and 2 company secretaries is to be formed. In how many ways can the team be selected?
The team can be chosen in 210 ways. Select 2 of the 7 chartered accountants in 21 ways and 2 of the 5 company secretaries in 10 ways, then multiply, since the two choices are independent. The figure 495 would ignore the required 2+2 split.
- A210Correct
- B495
- C35
- D420
Explanation
Choose 2 CAs from 7: 7C2 = 21. Choose 2 CSs from 5: 5C2 = 10. By the multiplication rule, the total is 21 × 10 = 210. The value 495 is 12C4, which ignores the required 2+2 split.
Did you get it right without looking?
One question tells you little. A timed set on Permutations and Combinations shows your real accuracy, how long you take and where you lose marks.
More Permutations and Combinations questions
- How many 5-digit numbers greater than 40000 can be formed using the digits 1, 2, 3, 4, 5, 6 without repetition of any digit?
- In how many ways can 6 persons be seated around a circular table if two particular persons, Anil and Bina, must NOT sit next to each other?
- Which expression equals 10C3 written using factorials?
- If nC2 = 45, how many ways can a team of 3 be selected from those n people?
- How many 3-digit even numbers can be formed using the digits 1, 2, 3, 4, 5, 6 if repetition of digits is not allowed?
- How many 3-digit even numbers can be formed using the digits 1, 2, 3, 4, 5, 6 without repeating any digit?