Sovardipk

2022-07-10

Nate has scores of 85, 91, 89, and 93 on four tests. What is the least number of points he can get on the fifth test to have an average of at least 90?

haingear8v

Expert

Step 1
Let x stand for the number of points on the fifth test.
Then his average score will be:
$\frac{85+91+89+93+x}{5}=\frac{358+x}{5}$
We want this to satisfy:
$\frac{358+x}{5}\ge 90$
Multiply both sides by 5 to get:
$358+x\ge 450$
Subtract 358 from both sides to get:
$x\ge 92$
So Nate needs at least 92 points.

Do you have a similar question?