Question

If p is the smallest prime factor of 511, then

a. 18 ≤ p ≤ 23
b. 10 ≤ p ≤ 17
c. 3 ≤ p ≤ 9
d. none of these

Answer 1

C.
`3 \le p \le 9`

Explanation:

The prime factor decomposition of 511 is
`7* 73`, where 7 is the smallest prime factor. Hence, the correct answer is C.