Multiple choice

The average weight of 10 students is 80 kg. If the heaviest and the lightest weights are not considered, the average is 81 kg. If the heaviest weight is 92 kg, find the lightest weight.

  1. 50

  2. 60

  3. 70

  4. 75
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Total weight of 10 students = 10 × 80 = 800 kg. Excluding heaviest (92 kg) and lightest (x), average of 8 students = 81 kg, so their total = 8 × 81 = 648 kg. Therefore 92 + x = 800 - 648 = 152, so x = 152 - 92 = 60 kg.

Keep practicing — related questions