Multiple choice

The average weight of 32 students of a class was 58.5kg. After 8 new students joined the class, its average weight Increased by 1.2 kg. What is the average weight of 8 new students who joined the class? (in kg)

  1. 62.5

  2. 64.5

  3. 65

  4. 63

  5. 63.5
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Total weight of 32 students = 32 * 58.5 = 1872. Total weight of 40 students = 40 * (58.5 + 1.2) = 40 * 59.7 = 2388. Weight of 8 new students = 2388 - 1872 = 516. Average = 516 / 8 = 64.5.

AI explanation

The original total weight of the 32 students is calculated using the average formula as 32 multiplied by 58.5 kg, which equals 1872 kg. After the 8 new students join, the total number of students becomes 40, and their new average weight of 59.7 kg results in a combined total weight of 40 multiplied by 59.7 kg, or 2388 kg. The total weight of the 8 new students is the difference between these totals, which is 2388 minus 1872, equaling 516 kg, and dividing this by 8 gives their average weight of 64.5 kg.

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