maria scored 72, 97, and 82 on her first three math tests. she wants to have a mean score of 82 for the…

Answer:

B. 77

Explanation:

Step1: Recall mean - score formula

The mean $\bar{x}=\frac{\sum_{i = 1}^{n}x_{i}}{n}$, where $\bar{x}$ is the mean, $x_{i}$ are the individual scores and $n$ is the number of scores. Here, $n = 4$ (three tests already taken and one more to go), and $\bar{x}=82$. Let the score on the fourth test be $x$. The sum of the first three scores is $72 + 97+82=251$.

Step2: Set up the equation

We know that $82=\frac{251 + x}{4}$.

Step3: Solve the equation for $x$

Multiply both sides of the equation by 4: $82\times4=251 + x$. So, $328=251 + x$.

Step4: Isolate $x$

Subtract 251 from both sides: $x=328 - 251=77$.