If in k+1 years from now John will be m years old, then how old was John...

[BTGmoderatorLU]

Source: Economist GMAT

If in k+1 years from now John will be m years old, then how old was John t-1 years ago?

A. m-k-t
B. m+k-t+2
C. m+k-t+1
D. k-m-t+2
E. k+t-m

The OA is A

[Brent@GMATPrepNow]

Source: Economist GMAT

If in k+1 years from now John will be m years old, then how old was John t-1 years ago?

A. m-k-t
B. m+k-t+2
C. m+k-t+1
D. k-m-t+2
E. k+t-m

The OA is A

In k+1 years from now John will be m years old
So, m - (k + 1) = John's PRESENT age

How old was John t-1 years ago?
So, m - (k + 1) - (t - 1) = John's age (t-1) YEARS AGO

Simplify m - (k + 1) - (t - 1) to get: m - k - t

Answer: A

Cheers,
Brent