vanessa wants a test average of atleast 90 and she has scores of 84, 91, and 89 on her first 3 tests. what score does she need on her final test
Let's call the score Vanessa needs on her final test "x".
To find the average score, we need to add up all four test scores and divide by 4.
The sum of the test scores is 84 + 91 + 89 + x.
To find the average, we divide this sum by 4.
(84 + 91 + 89 + x) / 4 = 90.
Multiplying both sides of the equation by 4, we have:
84 + 91 + 89 + x = 360.
Combining like terms on the left side, we have:
264 + x = 360.
Subtracting 264 from both sides of the equation, we have:
x = 360 - 264.
x = 96.
Therefore, Vanessa needs to score at least 96 on her final test to achieve an average score of 90.
To find the score Vanessa needs on her final test to achieve an average of at least 90, we can follow these steps:
Step 1: Add up all the scores Vanessa has for her first three tests:
84 + 91 + 89 = 264
Step 2: Determine the number of tests Vanessa has taken so far:
Vanessa has taken 3 tests.
Step 3: Set up the equation to find the test average:
(264 + x) / (3 + 1) ≥ 90
Where x represents the score Vanessa needs on her final test.
Step 4: Solve the equation for x:
(264 + x) / 4 ≥ 90
Multiply both sides of the equation by 4 to eliminate the fraction:
264 + x ≥ 360
Subtract 264 from both sides of the equation:
x ≥ 360 - 264
Simplify:
x ≥ 96
Therefore, Vanessa needs to score at least a 96 on her final test to achieve an average of at least 90 across all her tests.