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One coin is picked at random. What is the probability of picking a quarter or dime? Round the answerthe nearest hundredth of a percent.

One coin is picked at random. What is the probability of picking a quarter or dime-example-1
User Schemacs
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1 Answer

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Whenever we have "AND" in a probability question, it means "x" [multiplication].

When we have "OR" in a probability question, it means "+" [addition].

Here, we want Probability of Quarter [P(q)] OR Probability of Dime [P(d)].

So, we will add the individual probabilities.

Now,

Total Coins = 7 + 11 + 8 + 15 = 41

Number of Quarters = 7

Number of Dimes = 11

So, we find individual probabilities:

P(q) = 7/41

and

P(d) = 11/41

Now, we add them up:


\begin{gathered} P(q)+P(d)=(7)/(41)+(11)/(41) \\ =(18)/(41) \end{gathered}

To get percentage, we do the division and multiply by 100.

18 divided by 41 = 0.4390

Multiply by 100:

0.4390 * 100 = 43.90%

User Vladimir Ramik
by
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