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5 votes
The fountain contains 20 pennies and 9 dimes. A coin is randomly taken and not replaced. A second coin is randomly taken. What is the probability that both coins are pennies?

User Ben Patch
by
8.2k points

2 Answers

3 votes

Answer:

9 dimes

Explanation:

th fountai contains more that wat u would think but u mist move

User Ankitkumar Makwana
by
8.1k points
4 votes
Well, the first coin has chance
(20)/(29) to be a penny. When it is a penny, the only valid case (the other case gives 0 for the multiplications later, so it is ignored) gives
(19)/(28) chance for the second one to be a penny. The result is
(20*19)/(29*28), which is
(95)/(203), or about 46.80% (rounded to the first 2 decimals)
User IKriKan
by
8.4k points