Question

How many primes less than 1000 are divisible by 7?

none
1
more than 1 but less than 142
142
more than 142

Answer 1

142


(ten multiples till 70, 20 till 140, 30 till 210 and so on ........... 140 till 980. after this two more multiples of 7 i.e. 987 and 994)

Answer 2

If a number is prime, it is ONLY divisible by itself and 1.

So the only prime number divisible by 7 is the number 7 itself.

Hence the number of primes less than 1000 divisible by 7 is one: the number 7.