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Test 8 Section 7 - #17 (page 851)

We can BACKSOLVE this. It's weird that they spell out the numbers in the answer choices instead of just using numerals, but it doesn't matter.

Start with (C). If it's 3 years, then


should be equal to 3200. But is that true? No, it's 2560! That's too small...which means (and this is the tricky part) that we need to go in the direction of fewer years. Remember that the car is LOSING value over time, so if it's already too low, that means he's had it for too long.

So we try (B). If its 2 years, then 


should be 3200, and that IS true! (B) is our answer. 

Note: depending on which edition of the Blue Book you have, the printed answer in the key is WRONG on this one. I promise you that the answer is (B), but your book might say it's (C). My book does. Look at the very first page and hopefully you'll have a yellow sheet that makes all the silly corrections they forgot to make before they printed the book. If not, click the link in this paragraph to see for yourself.