Question

If the probability of rain on any given day in Pune city 50%, then what is the probability that it rains on exactly 3 days in a 5-day period?

• A. 8/125
• B. 5/16
• C. 8/25
• D. 2/25

Answer 1

The correct option is B 5/16

$Probabilitythatitrainsonanyday=\frac{1}{2}$

$anditdoes{n}^{\prime }train=1-\frac{1}{2}=\frac{1}{2}$

$Prob,thatitrainsonexactly3daysina5-dayperiod$

$={}^5{C}_3\times {\left(\frac{1}{2}\right)}^3\times {\left(\frac{1}{2}\right)}^2$

$=\frac{5}{16}$