Question

if the average of a,b and 9 is 13,what is the average of a+5, b-2 and 3?

Answer 1

(a+b+9)/3=13
a+b=39-9
a+b=30
(a+5+b-2+3)/3=x
a+b+6=3x
put a+b = 30 in this
we get
30+6=3x
36/3=x
x=12
the average of a+5,b-2,and 3 is 12.