Problem:
One student in a class of boys and girls is to be chosen to represent the class. Each student is equally likely to be chosen and the probability that a boy is chosen is of the probability that a girl is chosen. The ratio of the number of boys to the total number of boys and girls is
Answer Choices:
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Solution:
Since the selection is random, the number of boys is the number of girls. Thus there are boys for every girls, i.e., boys for every students. Alternately, let and be the number of boys and girls. Then and so