The average weight of 8 persons is increased by 2.5kg when one of them whose weight is 56kg is replaced by a new man. The weight of the new man is ?
Can you explain?
Average 2.5kg increased means total 8x2.5kg increased.
ie, an increase of 20kg.
The first person is replaced by the 2nd person with 20 kg extra weight.
So the weight of the new man is 56+20=76kg