This question is easier if you "solve" it rather than actually solve it. By this, I mean reasoning and educated guessing can save you a lot of time over solving it algebraically.

First, you know that truck sales in 1996 (denote as T) were higher than car sales in 1996 (denote as C) (car sales decreased by more than truck sales increased, and yet total revenues still increased, therefore, the increase from truck sales must have been more than the decrease from car sales)

This eliminates choices C, D, and E.

From A, and B, plug in the answer choices...

A:

Assume C = 100, T = 200, total revenue = 300
In 1997, C = 89 (89%*100), T = 214 (107%*200), total revenue = 303

This is a 1% increase.

Therefore, A is the answer.


If you still want to know how to solve it algebraically, I'd be happy to detail the tedious process... but it's not fun, and the numbers aren't kind. 8)

C7= Revenue of Car 1997, T7=Revenue of Truck 1997
C6=Revenue of Car 1996, C6=Revenue of Truck 1996

C7=89/100(C6) -------1
T7=107/100(T6)--------2
C7+T7=101/100(C6+T6)--------3
Add eq 1 and eq2 and put into eq 3
101/100(C6+T6)=89/100 C6 + 107/100 T6
Solve it
C6/T6=1/2
so Answer is A