A box contains 4 red chips and 2 blue chips. If two chips are selected at random without replacement, what is the probability that the chips are different colors?
A. 1/2
B. 8/15
C. 7/12
D. 2/3
E. 7/10
OA B
Source: Magoosh
A box contains 4 red chips and 2 blue chips. If two chips are selected at random without replacement,
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P(different colors) = P(1st chip is red and 2nd chip is blue OR 1st chip is blue and 2nd chip is red)BTGmoderatorDC wrote: ↑Thu Nov 04, 2021 10:16 pmA box contains 4 red chips and 2 blue chips. If two chips are selected at random without replacement, what is the probability that the chips are different colors?
A. 1/2
B. 8/15
C. 7/12
D. 2/3
E. 7/10
OA B
Source: Magoosh
= P(1st chip is red and 2nd chip is blue) + P(1st chip is blue and 2nd chip is red)
= P(1st chip is red) x P(2nd chip is blue) + P(1st chip is blue) x P(2nd chip is red)
= 4/6 x 2/5 + 2/6 x 4/5
= 8/30 + 8/30
= 16/30
= 8/15
Answer: B
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To satisfy the requirement, we must obtain either R-B or B-R. Thus, we need to determine:BTGmoderatorDC wrote: ↑Thu Nov 04, 2021 10:16 pmA box contains 4 red chips and 2 blue chips. If two chips are selected at random without replacement, what is the probability that the chips are different colors?
A. 1/2
B. 8/15
C. 7/12
D. 2/3
E. 7/10
OA B
Source: Magoosh
P(red) x P(blue) + P(blue) x R(red)
4/6 x 2/5 + 2/6 x 4/5 = 2/3 x 2/5 + 1/3 x 4/5 = 4/15 + 4/15 = 8/15.
Answer: B
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