Question

Alan has 3 quarters and 7 dimes in his pocket. If he takes out a coin, puts it back in his pocket, and then takes out a coin again, what is the probability that both coins are dimes?

Answer 1

Probability of picking a dime both times = (7/10)^2 = 49/100, or 0.49

Explanation:

Picking with replacement, twice from 3 quarters and 7 dimes.

Probability of picking a dime each time = 7/10.

Probability of picking a dime both times = (7/10)^2 = 49/100, or 0.49