Question

Mean of three no is 8 .the meanof those 3 no and x is 7.findx

Answer 1

mean of 3 numbers = (sum of three numbers)/3

8 =(sum of three number)/3 

8 × 3 = sum of three numbers

24 = sum of three numbers

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Mean of 3  numbers with x = (sum of 3 numbers  + x)/4 

7 = (24 + x)/4 

7  ×  4 = 24 + x 

28 - 24= x 

4 = x 


i hope this will help you


-by ABHAY

Answer 2

mean of 3number=8
sum of numbers=8×3
=24
further
meanof4 numbers(3+x)=7
sum of numbers. =7×4
=7×4
=28
then
24+x. =28
x. =28-24
=4 Ans