Probability = desired/total. There are 26 total students in the class.
A. There are 13 people who wear glasses. 13/26 = 1/2 = 50%
B. Boy or wears glasses is 12 boys, and 8 more (girls) who wear glasses for a total of 20. 20/26 = 10/13 = 76.9%
C. There are 5 people who are boys and wear glasses. 5/26 = 19.2%.
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