There are three sections A, B and C in class X with 25, 40 and 35 stud

1.	There are three sections A, B and C in class X with 25, 40 and 35 students respectively.The average marks obtained by section A, Band C are 70%, 65% and 50% respec-tively. Find the average marks of entire class X
Answer» Let us assume that the total marks are 100. Then the average marks obtained by each class A,B,and C is 70,65 and 50. Then the total marks obtained by students of A,B and C are 7025, 6540 and 50*35 So the average of all the classes is, (70×25+65×40+50×35) / (25+40+35) So the average of all classes is 61%

There are three sections A, B and C in class X with 25, 40 and 35 students respectively.The average marks obtained by section A, Band C are 70%, 65% and 50% respec-tively. Find the average marks of entire class X

Answer»

Let us assume that the total marks are 100.

Then the average marks obtained by each class A,B,and C is 70,65 and 50.

Then the total marks obtained by students of A,B and C are 70*25, 65*40 and 50*35

So the average of all the classes is,

(70×25+65×40+50×35) / (25+40+35)

So the average of all classes is 61%