Help! Pls......

Ploy is hoping to get a 90% on her math test, but she would be happy with any score within 10 points of 9. Find the range of score ploy would be happy with on her math test.

-m.

"Within ten points of nine" is a bit hard to understand. The most obvious way is that it's a 100-point exam, and 90% +/- 10 percentiles, or 90 points +/- 10 points, means that 80 pts plus is enough?