Question

A book has pages numbered from 1 to 85. What is the probability that the sum of the digits on the page is 8, if a page is chosen at random?

• A. $\frac{6}{85}$
• B. $\frac{7}{85}$
• C. $\frac{9}{85}$
• D. $\frac{8}{85}$

Answer 1

The correct option is C

$\frac{9}{85}$

Total number of pages in the book = 85
Favorable outcomes are: 8, 17, 26, 35, 44, 53, 62, 71, 80.
$\therefore$ No. of favorable outcomes = 9

Let $E$ be the event of getting sum of the digits on the page is 8.

$\text{Probability P(E)}$ = $\frac{\text{Number of outcomes favorable to E}}{\text{Number of all possible outcomes of the experiment}}=\frac{9}{85}$