sonya's average in math class is an 84 after 3 tests. what must she get on the next test to raise her average to an 88?
answered by Steve here
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To determine what Sonya must get on the next test to raise her average to an 88, we need to consider the current average and the number of tests taken so far.
Sonya has taken 3 tests, and her current average is 84. To calculate the sum of her scores on the 3 tests, we would multiply the average (84) by the number of tests (3): 84 x 3 = 252.
Now, we need to find out what score Sonya needs on the next test to raise her average to 88. Let's denote this score as "x." To calculate the new sum of her scores (including the next test score), we would add the sum of her previous scores (252) and the next test score (x): 252 + x.
Since her average is calculated by dividing the sum of her scores by the number of tests taken, we can set up the following equation:
(252 + x) / 4 = 88
To solve for x, we can start by multiplying both sides of the equation by 4 to eliminate the denominator:
252 + x = 88 * 4
Simplifying both sides of the equation:
252 + x = 352
Next, to isolate x, we subtract 252 from both sides of the equation:
x = 352 - 252
Simplifying further:
x = 100
Therefore, Sonya needs to get a score of 100 on her next test in order to raise her average to an 88.