lheiannie07 wrote:Mr. Yutaro's class contains 5 boys and 11 girls. If two students are chosen, one at a time, from the class, what is the probability that a boy and a girl are chosen?
A. 9/48
B. 9/20
C. 11/24
D. 27/48
E. 13/16
P = (good outcomes)/(all possible outcomes).
All possible outcomes:
From 16 students, the number of ways to choose 2 = 16C2 = (16*15)/(2*1) = 120.
Good outcomes:
A good outcome consists of 1 boy and 1 girl.
Of the 16 students, 5 are boys, 16 are girls.
Thus:
Number of options for the boy = 5.
Number of options for the girl = 11.
To combine these options, we multiply:
5*11 = 55.
Resulting probability:
(good outcomes)/(all possible outcomes) = 55/120 = 11/24.
The correct answer is
C.
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