Question

The mean of marks of 5 students are 70 the marks of four students are 50, 60, 70, it not find the marks of 5th student

Answer 1

where
bytai naa. oodhd

Answer 2

Here is the answer ,
let the marks of 5 student be x
It is given that mean of 5 student=70
mean of the four student=50,60,70
mean=sum of all observations/number of observations
This implies,
70=50+60+70+X/4
70=200+X/4
70*4=200+X
280=200+X
X=280-200
X=80
thus, the fifth student got 80 marks.

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