Correct option is B
Given:
The average weight of 7 people increases by 5 kg when a new person comes in place of one of them weighing 55 kg.
Formula Used:
Weight of new person = weight of the person being replaced + total change in weight
Solution:
Weight of the person replaced = 55 kg
Total change in weight due to new person = 5 kg per person for 7 people
Total change in weight due to new person = 5 × 7 = 35 kg
Weight of new person = 55 + 35 = 90 kg