Susan’s test scores are 93, 85, 88, and 90. What does she need to score on the next test to raise her average to 90?
93 + 85 * 88 + 90 = 356
500*0.9 = 450
450 - 356 = ?
93 + 85 + 88 + 90 = 356
To find out what Susan needs to score on the next test to raise her average to 90, we need to calculate her current average and then determine the score needed.
Step 1: Calculate Susan's current average
To calculate the average, we sum up all her test scores and divide by the number of tests.
Average = (93 + 85 + 88 + 90) / 4 = 356 / 4 = 89
So, Susan's current average is 89.
Step 2: Determine the score needed
To raise her average to 90, we need to find the score that, when added to her current total, gives an average of 90.
Average = (93 + 85 + 88 + 90 + x) / 5 = 90
Now, we'll solve for x (the score needed).
Multiply both sides of the equation by 5:
93 + 85 + 88 + 90 + x = 450
Combine like terms:
356 + x = 450
Subtract 356 from both sides:
x = 450 - 356
x = 94
So, Susan needs to score at least 94 on the next test to raise her average to 90.