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A box contains 6 black balls and 4 white balls. If two balls are selected at random without replacement, what is the pro

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A box contains 6 black balls and 4 white balls. If two balls are selected at random without replacement, what is the pro

by M7MBA » Thu Oct 29, 2020 12:35 pm

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A box contains 6 black balls and 4 white balls. If two balls are selected at random without replacement, what is the probability that both balls are white?

A. 7/90
B. 3/25
C. 2/15
D. 4/25
E. 4/9

Answer: C

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Re: A box contains 6 black balls and 4 white balls. If two balls are selected at random without replacement, what is the

by jhavyom » Sun Nov 01, 2020 1:13 am
A box contains 6 black balls and 4 white balls. If two balls are selected at random without replacement, what is the probability that both balls are white?

Number of ways of selecting 2 white balls from 4 white balls without replacement = 4C2 = 6 ways
Number of ways of selecting 2 balls from a box, which contains 6 black balls and 4 white balls, without replacement = 10C2 = 45 ways

Probability that both balls are white = 6/45 = 2/15

Choice C is the answer.
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Re: A box contains 6 black balls and 4 white balls. If two balls are selected at random without replacement, what is the

by Scott@TargetTestPrep » Thu Nov 05, 2020 3:37 pm
M7MBA wrote: ↑
Thu Oct 29, 2020 12:35 pm
 A box contains 6 black balls and 4 white balls. If two balls are selected at random without replacement, what is the probability that both balls are white?

A. 7/90
B. 3/25
C. 2/15
D. 4/25
E. 4/9

Answer: C

Solution:

There are 10 balls in the box. The probability that the first ball drawn will be white is 4/10, and the probability that the second ball will also be white is 3/9. Thus, the probability of selecting two white balls, without replacement, is 4/10 x 3/9 = 2/5 x 1/3 = 2/15.

Answer: C

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