There are 20 students in a class. In total, 10 of them have black hair, 5 of them wear glasses, and 3 of them both have black hair and wear glasses. How many of the students have black hair but do not wear glasses?
A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.
Since 10 students have black hair and 3 students have black hair and wear glasses, then a total of 10−3=7 students have black hair but do not wear glasses.
Source: Omni-MATH,
licensed Apache-2.0.
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