Kat gets a 95% on her first math test and an 80% on her second math test. If she wants an average grade of at least 90% in her math class, what does she need to get on her third final math test?
Let's be accurate as possible and think first.
95
Let x = the percent needed on her third math test.

(95 + 80 + x) / 3 = 90.

(95 + 80 + x) = 270.

x = 270 - 95 - 80.

x = 95.

.

Thus, the answer is 95