Question

How many different committees of 7 can be formed from 10?

Answer 1

Let,

n = the total number of elements, in this case 10

r = the number being picked, in this case 7

Use the combination formula:

= (n!/r!(n - r)!)

= (10!)/(7!(10 - 7)!)

= (10!)/(7!3!)

= 120

Answer 2

Answer:

we have to select 7 out of 10 ....

10c7 = 10!/7!3! = 10*8*9/3*2 = 120 (Ans)