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A box contains 10 pairs of shoes (20 shoes in total). If two
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19 Nov 2019, 11:06
19 Nov 2019, 11:06
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Question Stats:
64% (00:50) correct
35% (01:16) wrong based on 39 sessions
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A box contains 10 pairs of shoes (20 shoes in total). If two shoes are selected at random, what is the probability that they are matching shoes?
[A] \(\frac{1}{190}\)
[B] \(\frac{1}{20}\)
[C] \(\frac{1}{19}\)
[D] \(\frac{1}{10}\)
[E] \(\frac{1}{9}\)
[A] \(\frac{1}{190}\)
[B] \(\frac{1}{20}\)
[C] \(\frac{1}{19}\)
[D] \(\frac{1}{10}\)
[E] \(\frac{1}{9}\)
Re: A box contains 10 pairs of shoes (20 shoes in total). If two
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22 Nov 2019, 11:47
22 Nov 2019, 11:47
2
Expert Reply
probability to choose any shoe out of 20 is 20/20
probability to choose its pair is 1 out of 19 i.e 1/19.
thus (20/20)*(1/19) = 1/19
probability to choose its pair is 1 out of 19 i.e 1/19.
thus (20/20)*(1/19) = 1/19
Re: A box contains 10 pairs of shoes (20 shoes in total). If two
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15 Jan 2024, 07:26
15 Jan 2024, 07:26
favorable outcomes/ total outcomes
Favorable outcomes = 10C1 (10 pairs and we select 1 out of 10)
total outcomes = 20C2 = 190
=10/190 = 1/19
Favorable outcomes = 10C1 (10 pairs and we select 1 out of 10)
total outcomes = 20C2 = 190
=10/190 = 1/19
