Multiple choice

In a class, there are 45 students. 30 of them are boys. The average weight of all the boys in a class is 50 kg and the average weight of the girls is 40 kg. What would be the average weight of all the students in the class?

  1. 46.67 kg

  2. 45 kg

  3. 44 kg

  4. 42.67 kg

  5. 41.25 kg
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A Correct answer
Explanation

Boys = 30, Girls = 15. Total weight = (30 * 50) + (15 * 40) = 1500 + 600 = 2100. Average = 2100 / 45 = 46.67 kg.

AI explanation

The total weight of the 30 boys is 30 times 50 kg, which equals 1500 kg. Since there are 45 students in total, there are 15 girls, and their total weight is 15 times 40 kg, which equals 600 kg. Using the average formula, the combined average weight is the sum of both totals divided by the total number of students: (1500 + 600) / 45. This gives 2100 / 45, which equals 46.67 kg.

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