a relativistic fly flies at 0.7c in the same direction as a car traveling at 0.8c. According to the driver of the car, how quickly will the fly approach the car?

To solve this problem, I applied the relativistic velocity addition formula: $$ u' = \frac{u - v}{1 - \frac{uv}{c^2}} $$

where u = 0.7c and v = 0.8c. The answer that I get is 0.23c. however, the answer in my book is 0.96c. I was wondering which answer is correct, as I think the book's answer could be wrong.