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Michael has 3 quarters, 2 dimes, and 3 nickels in his pocket. He randomly draws two coins from his pocket, one at a time, and they are both dimes. He says the probability of that occurring is 1 4 because 2 of the 8 coins are dimes. Is he correct

1 Answer

4 votes

Answer:

No, he is wrong

Explanation:

To find that probability, the first thing we need to know is the total number of coins present.

Mathematically, that would be 3 + 2 + 3 = 8

Since there are 8 coins, the probability of selecting a dime is number of dimes/total number of coins = 2/8 = 1/4

The probability we want to work with is that the two selections are dimes, let’s say with replacement.

That means; first selection is a dime and second selection is also a dime

Mathematically in probability, the term and means that we have to multiply our results.

So the probability that both are dimes would be 1/4 * 1/4 = 1/16

And this makes his answer wrong

User Felix Dombek
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