Question

The average weight of a,b & c is 45 kg.if the average weight of a & b be 40 kg & that of b & c be 43 kg, then the weight of b is

Answer 1

a+b+c/3=45
a+b+c=45×3=135

a+b=80
a=80-b

b+c=86
c=86-b

80-b+b+86-b=135
166-b=135
-b= -31
b=31 kg