Question

What is the value of N(N(30))?

N(x) is the no. of primes numbers less than x.

a) 3  b) 4  c) 23   d) 29

Answer 1

N(x) is the no. of primes numbers less than x.

N(30) = 10
N(N(30)) = N(10) = 4

Answer is (b)