The average weight of 10 persons increases by 3 kg when a new person comes in place of one of them weighing 55 kg. The weight of the new person is:
Answer & explanation
Correct answer: option 1
Let the average of 10 people be x kg
And the weight of the new person be y kg
Sum of 10 people weight is
10× x = 10x kg
When the person is replaced.
10x + y - 55 = 10 × (x + 3)
10x + y - 55 = 10x + 30
y = 55 + 30 = 85 kg
∴ The weight of the new person is 85 kg.