Question

The smallest rational number by which 1/3 should be multiplied so that its decimal expansion terminates after one place of decimal , is
a)3/10
b)1/10

Answer 1

Let x = p/q be a rational number, such that the prime factorization of q is of the form 2n 5m, where n, m are non - negative integers.

Then x has a decimal expansion which terminates.

So 1/3 should be multiplied by 3/10 so that it is in the form of 2n5m.