carcass wrote:

John is 20 years older than Brian. 12 years ago, John was twice as old as Brian. How old is Brian?

what's wrong with this word translation ??'

J= B + 20

J-12=2 (B+8)

We can let John’s age today = j and Brian’s age today = b, and we can create the following equation:

j = b + 20

We see that 12 years ago, John’s age was (j - 12) and Brian’s age was (b - 12). We know that at that time, John was twice as old as Brian. Thus, we have:

j - 12 = 2(b - 12)

j - 12 = 2b - 24

j = 2b - 12

We have two equations for b. Equating them, we have:

b + 20 = 2b - 12

32 = b

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