Question

Total age of A & B is 12yrs more than total age of B & C. C is how many year younger than A ?

Answer 1

any idea?

Answer 2

a + b = 12 + (b + c)

You can write it like this :
a+b = n
12 + (b+c) = n

Answer 3

For: a+b = n
b - n = a

For: 12 + (b+c) = n
b - n + 12 = c

Answer 4

How about (a+b)>(b+c) & A>C

Answer 5

what are you asking about?
From here, you already get the answer:

(i) b - n = a
(ii) b - n + 12 = c

substitute a for (b - n)

Answer 6

I want answer in terms of integer.

Answer 7

He's trying to help you, instead of directly answering (which is against OS rules). It seems as if something is wrong though... Here's what I get:
\[A + B = B + C + 12\]
Move the B to the other side:
\[A + B - B = C + 12, A = C + 12\]
Which shows you what the answer would be. Make sense?

Answer 8

I too have got the same equation earlier before posting this question on OS, but I guess question has insufficient data to exactly tell that C is how many year younger than A ?

Answer 9

If A = C + 12, then A's age is 12 more than C's. Doesn't that seem to be enough?