Question

the average weight of 12 crewmen in a boat is increased by 1/3kg. when one of the crewmen whose weight is 55 kg is replaced by a new man. what is the weight of that new man?​

Answer 1

Answer:

let the average of 12 crewman be X

Total age of crewman = (average×total no. of crewman)

Total age of 12 crewman=12×X

=12X

total age when a man of weight 55left

the boat =12X-55

let the age of new crewman be Y

when he replace the man average increase by 1/3kg

A/Q

12X-55+Y=12(X+1/3)

12X-55+Y=12X+4

Y=12X-12X+4+55

Y= 59

hence the weight of new crewman is 59 kg