Question

A+B = 250 ,B+C= 320 ,D(B-C)= 100 ,C+A=220 WHAT IS THE VALUE OF D ??

Answer 1

Here is your answer.

A+B=250
or, A=250-B. ------------(i)

Also,C+A=220
or, A= 220-C. ---------------(ii)

Comparing (i) and (ii),
250-B=220-C
or,B-C= 250-220 =30

Therefore, D-(B-C)=100
or,D-30=100
or,D=100+30 = 130.

Hope it helps you.