Question

A number is selected at random from first 50 natural numbers. The probability that selected number is a multiple of 3 or 4 is:

• A. $\frac{12}{25}$
• B. $\frac{14}{25}$
• C. $\frac{14}{50}$
• D. $\frac{8}{25}$

Answer 1

The correct option is A $\frac{12}{25}$

$n\left(s\right)=1,2,3,....,50$
multiple of $3=3,6,9,....,48$
number of multiples of $3=16$
number of multiples of $4=12$
number of multiples of 3 and 4$=4$
$\therefore n\left(A\right)=16+12-4=28-4=24$
$P\left(E\right)=\frac{24}{50}=\frac{12}{25}$