Calculate Sarah's Minimum Score

Question

Question: In order to graduate, Sarah has to make an average score of at least 90. If he made 95 and 94 on his first two tests. What should his minimum score be on her final test in order to graduate?

Answer 1

Answer: To find the answer to this question, we need to find the average of the three tests.

Average = Sum of Test Scores divided by the Number of Tests

In the question, the average was given. Sarah needs at least a 90.

So, 90 = Sum of Test Scores divided by Number of Tests

Since there are only 3 tests, and the first two tests scores were 95 and 94, we then know that the Sum of Test Scores $= 95 + 94 + x.$

Now that we found the sum of the test scores, we need to divide by the number of tests, which is 3.

So the equation should look like this:

$$90=\frac{95+94+x}3.$$

To solve for this equation, we first need to multiple both sides by 3.

So the equation should look like this:

$$270=189+x.$$

After this, you would subtract 189 from both sides, to get the final answer for x.

$$x = 81. $$

Sarah needs to at least get an 81 on her final test in order to graduate.