Question

# If then (n,r) is

- (7,4)
- (6,2)
- (8,4)
- (10,3)

Hint:

### To find the value of n and r first we will use the formula and we will get two equations then we will equate them and get the values.

## The correct answer is: (10,3)

### Given,

from equ 1 and 2

720(n-r)! =120 r! (n-r)!

6=r!

r=3

putting r=3 in equ 1

### Related Questions to study

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