A class has 90 students. If the ratio of boys and girls is 7:8, find the number of boys in the class.
Correct answer: B. 42
- A. 48
- B. 42
- C. 60
- D. 70
Explanation
The total ratio parts are 7 + 8 = 15, so one part represents 90 students ÷ 15 = 6 students. Boys = 7 × 6 students = 42 students. The likely mistake is option c, 60 students, from assigning the larger ratio, 8 parts, to the boys.
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