.
The probability is the ratio of the number of all possible pairs chosen from 15 girls
to the number of all possible pairs chosen from all 15+10 = 25 students.
The numerator is = = 15*7 = 105.
The denominator is = = 25*12 = 300.
The ratio, i.e. the probability under the problem's question, is P = = = = 0.35 = 35%. ANSWER
Solved.
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- Elementary Probability problems related to combinations
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