On three 150point geography tests, you earned grades of 88%, 94%, and 90%. The final test is worth 250 points. What percent do you need on the final to earn 93% of the total points on all tests?
(88+94+90)*150+250x = 93*(3*150+250)
x = 97.2
good luck with that, judging from previous scores...
To find out the percent you need on the final test to earn 93% of the total points on all tests, you can follow these steps:
Step 1: Calculate the total points you received on the three tests.
To calculate the total points, add the points earned on each test together:
88% of 150 points = 0.88 * 150 = 132 points
94% of 150 points = 0.94 * 150 = 141 points
90% of 150 points = 0.90 * 150 = 135 points
Total points earned on the three tests = 132 + 141 + 135 = 408 points.
Step 2: Calculate the total points possible for all tests.
The total points possible for the three 150-point tests are 3 x 150 = 450 points.
Including the final test, the total points possible becomes 450 + 250 = 700 points.
Step 3: Determine the points needed to achieve 93% of the total points.
To earn 93% of the 700 total points, the points needed would be:
0.93 * 700 = 651 points.
Step 4: Calculate the points needed on the final test.
The points needed on the final test is the difference between the points needed (651) and the points earned (408) on the previous tests:
651 - 408 = 243 points needed on the final test.
Step 5: Determine the required percent on the final test.
To calculate the percent needed on the final test, divide the points needed (243) by the points possible on the final test (250) and multiply by 100%:
(243 / 250) * 100% = 97.2%.
Therefore, you would need to score at least 97.2% on the final test to earn 93% of the total points on all the tests.