Question

What is the probability of a number picked from first twenty natural numbers is even composite number?

Answer 1

The composite even numbers upto $20$ are-

$4,6,8,10,12,14,16,18,20$

Total number of even composite numbers upto $20=9$

Therefore,

Total number of possible outcomes $=20$

No. of favourable outcomes $=9$

$\therefore$ Probability of selecting a even composite number $=\frac{\text{No. of favourable outcomes}}{\text{Total no. of possible outcomes}}=\frac{9}{20}$

Hence the correct answer is $\frac{9}{20}$.