The average weight of students of section A and B having 40 students each is 45.5 kg and 44.2 kg respectively. Two students of section A having average weight 48.75 kg were shifted to section B and 2 students of section B were shifted to section A, making the average weight of both the sections equal, What is the average weight(in kg) of the students who were shifted from section B to section A?
Answer & explanation
Correct answer: option 1
Sum of weights of students of section A = 45.5 x 40 = 1820 kg
Sum of weights of students of section B = 44.2 x 40 = 1768 kg
Weight of students who are shifted from A to B = 48.75 x 2 = 97.5 kg
Lets assume weight of students shifted from section B to A = x
New sum weight of section A = 1820 - 97.5 + x = 1722.5 + x
New sum of weight of section B = 1768 + 97.5 - x = 1865.5 - x
Given , 1722.5 + x = 1865.5 - x
⇒ x = 71.5
Average weight of students who shifted from B to A = \(\frac{71.5}{2}\) = 35.75 kg