Chapter 13, Problem 24RE

To determine

To find: What is the probability that the bill will be a $\$1$ bill, If you pick a bill at random?

Answer to Problem 24RE

$P\left(\$1 bill\right) = \frac{4}{9}$

Explanation of Solution

Given:

You have four $\$1$ bills, three $\$5$ bills, and two $\$10$ bills in your wallet.

Formula used:

$P\left(E\right) = \frac{n\left(E\right)}{n\left(S\right)}$

Calculation:

Number of $\$1$ bill $= 4$.

Number of $\$5$ bill $= 3$.

Number of $\$10$ bill $= 2$.

$n\left(S\right) = 4 + 3 + 2 = 9$

$n\left(\$1 bill\right) = 4$

$P\left(E\right) = \frac{n\left(E\right)}{n\left(S\right)}$

$P\left(\$1 bill\right) = \frac{4}{9}$