math
posted by Brandon on .
on 3 tests you earned grades of 88%,94%,and 90%. Each test was worth 150points. The final exam is worth 250 points. How many points do u need on the final exam to earn 93% of the total points on tests? What percent do you need on the final?

Let's figure the total number of points you've earned.
0.88 * 150 = 132
0.94 * 150 = 141
0.9 * 150 = 135
Total points = 408
450 + 250 = 700 points possible
0.93 * 700 = 651 points you need to have an over all average of 93%
651  408 = 243 points needed on the final exam 
243/250 = 97.2% needed on final exam