Question

The number of oranges that Joe has is a multiple of 6. When he sells one orange, the number of oranges is a multiple of n. If n is a positive integer less than 10, how many possible values are there for n?

Answer 1

2 is the correct answer!

Answer 2

2

Explanation:

The number of oranges he has is a multiple of 6, so the number can be

6, 12, 18, 24, 30, 36, 42, 48, 54, etc.

He sells one orange, so now he an have:

5, 11, 17, 23, 29, 35, 41, 47, 53, etc.

All numbers above up to 53 are multiples of 1, so n can be 1.

Also 5 and 35 are multiples of 5, so n can be 5.

All numbers other than 5 and 35 are prime.

Answer: 2