Exams › SSC CGL (Prelims) › General
The average weight of 30 students in a class is 50 kg. If the weight of the teacher is added, the average rises to 51 kg. What is the teacher's weight?
- 75 kg
- 78 kg
- 80 kg
- 81 kg
Correct answer: 81 kg
Solution
The total weight of 30 students is \(30\times 50=1500\) kg. After adding the teacher, average becomes 51 kg for 31 people, so total weight = \(31\times 51=1581\) kg. Teacher's weight = \(1581-1500=81\) kg.
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