Question

steven received scores of 70, 95, and 80 on his last three math tests. he needs a mean test score of 80 to qualify for the math team. how many points does he need on his last test to qualify for the team?
steven needs dropdown total points to have a mean score of 80.
steven has dropdown points so far.
steven needs to score at least dropdown points on his last test to qualify for the team.
dropdown options: 70, 75, 80, 85

Explanation:

Step1: Calculate total points needed

The formula for the mean $\bar{x}=\frac{\sum_{i = 1}^{n}x_{i}}{n}$. Here, $n = 4$ (since there are 4 tests in total) and $\bar{x}=80$. So the total points needed $\sum_{i=1}^{4}x_{i}=n\times\bar{x}=4\times80 = 320$.

Step2: Calculate points so far

Steven's scores are $70$, $95$, and $80$. The sum of these scores is $70 + 95+80=245$.

Step3: Calculate points needed on last test

Let $x$ be the score on the last test. We know that $245 + x=320$. Solving for $x$, we get $x=320 - 245=75$.

Answer:

Steven needs $320$ total points to have a mean score of $80$. Steven has $245$ points so far. Steven needs to score at least $75$ points on his last test to qualify for the team.