The mean weight of a class of 20 students is 48 kg. Two more students weighing 60 kg and 58 kg respectively join the class. What is the mean weight of the class now ?

Dear Anjali,

[Equation]

Mean(Average) weight of a class = 48 kg
Total no. of students = 20 students
So,total weight of the class = Average * Total Quantity
=?(48 * 20) kg
=?960 kg

A/Q , Two students join the class
So,Weight of 1st student = 60 kg
Weight of 2nd student = 58 kg
Total weight of both of them = ( 60 + 58 ) kg = 118 kg

Now,
Total no. of students = 20 + 2 = 22 students
Total weight of class =
= Class weight + New students weight
=?960kg + 118kg
=?1078kg

Therefore,
Mean weight of class now =
=?22 students total weight / 22
=?1078 kg / 22
=?49 kg (Ans)

Thus , mean weight of class now = 49 kg (Ans)

Hope your doubts are clear.
Best wishes.

Regards,

The question mark is showing in the answer is just by mistake.I am sending it again.

Dear Anjali,

[Equation]

Mean(Average) weight of a class = 48 kg
Total no. of students = 20 students
So,total weight of the class = Average * Total Quantity
=(48 * 20) kg
=960 kg

A/Q , Two students join the class
So,Weight of 1st student = 60 kg
Weight of 2nd student = 58 kg
Total weight of both of them = ( 60 + 58 ) kg = 118 kg

Now,
Total no. of students = 20 + 2 = 22 students
Total weight of class =
= Class weight + New students weight
= 960kg + 118kg
= 1078kg

Therefore,
Mean weight of class now =
= 22 students total weight / 22
= 1078 kg / 22
= 49 kg (Ans)

Thus , mean weight of class now = 49 kg (Ans)

Hope your doubts are clear.
Best wishes.

Regards,