# Angela math test scores so far are as follows: 87, 96, 82, 77. What score must Angela make on the final test in order to have a test average of 88?

Let $x$ be the score of the final test then

$\frac{87 + 96 + 82 + 77 + x}{5} = 88 \implies x = 98$

Sep 16, 2015

I found $98$

#### Explanation:

Considering an average of $n$ scores:

$\frac{\Sigma \text{scores}}{n} = \frac{87 + 96 + 82 + 77 + x}{5} = 88$
you get:
$342 + x = 5 \times 88$
$x = 440 - 342 = 98$

Sep 16, 2015

Angela must score 98 in her final test.

#### Explanation:

Let $x$ represent the score that Angela gets on her final test.

The average of all 5 of the tests can be found by computing,

$\overline{x} = \frac{87 + 96 + 82 + 77 + x}{5} = 88$

from this we just use algebra and solve for $x$.

$\frac{342 + x}{5} = 88$
$x = \left(88 \times 5\right) - 342$
$x = 98$

Hope it helps :)