A student has test scores of 75, 80, and 90. What score does the student need on the next test to achieve an average of 85?
Understand the Problem
The question is asking what score a student needs on their next test in order to achieve an average of 85 with their current test scores of 75, 80, and 90. To solve this, we will calculate the total score needed for four tests to average 85 and determine the score required on the fourth test.
Answer
$95$
Answer for screen readers
The score needed on the next test is $95$.
Steps to Solve
- Calculate total score needed for the average To find the total score needed for four tests to average 85, we use the formula for average:
$$ \text{Average} = \frac{\text{Total Score}}{\text{Number of Tests}} $$
Rearranging gives us:
$$ \text{Total Score} = \text{Average} \times \text{Number of Tests} $$
So,
$$ \text{Total Score} = 85 \times 4 = 340 $$
- Sum the current test scores Now, we need to sum the current test scores:
- Current scores: 75, 80, and 90
Adding these gives:
$$ 75 + 80 + 90 = 245 $$
- Determine the score needed on the next test To find out what the student needs to score on the next test, we subtract the total score of the current tests from the total score needed:
$$ \text{Score Needed} = \text{Total Score} - \text{Current Total} $$
Substituting in the values gives:
$$ \text{Score Needed} = 340 - 245 = 95 $$
The score needed on the next test is $95$.
More Information
This means the student must score $95$ on their next test in order to achieve an average of $85$ across all four tests. Achieving such a score can be challenging but is attainable with proper preparation.
Tips
- Failing to correctly calculate the total score needed for the desired average.
- Not summing the current test scores accurately.
- Forgetting to properly subtract the current total from the total needed.
AI-generated content may contain errors. Please verify critical information
