Question

# A wallet contains 1 five-cent coin, 1 ten-cent coin, 2 twenty-cent coins, and 2 fifty-cent coins. What is the expected value if you randomly select 1

Probability and combinatorics
A wallet contains 1 five-cent coin, 1 ten-cent coin, 2 twenty-cent coins, and 2 fifty-cent coins. What is the expected value if you randomly select 1 coin?

2021-06-18

The expected value can be calculated by multiplying the probability of each event times the value of that event.
2Five cent coin: $$\displaystyle\frac{{1}}{{6}}{x}{0.05}={0.00833333333}$$
Ten cent coin: $$\displaystyle\frac{{1}}{{6}}{x}{0.10}={0.016666666}$$
Twenty five cent coin: $$\displaystyle\frac{{1}}{{3}}{x}{0.25}={0.0833333333}$$
Fifty cent coin: $$\displaystyle\frac{{1}}{{3}}{x}{0.50}={0.166666667}$$
$$30.00833333333 + 0.0166666667 + 0.0833333333 + 0.166666667$$