Answer:
D. 95
Explanation:
The average is also known as the mean. To find the mean, you need to add all the values, then divide them by the number of terms:
1 2 3
1+2+3
6/3=2
The mean for the example would be 2. Now, using your values, you can use the options to see which one gives you an average of 90:
A.) 85
![80+100+85+85=350\\(350)/(4) =87.5](https://img.qammunity.org/2021/formulas/mathematics/middle-school/mkenmrenr9a133p9fz4vactrj8n9rnjzaq.png)
B.) 90
![80+100+85+90=355\\(355)/(4)= 88.75](https://img.qammunity.org/2021/formulas/mathematics/middle-school/p2uzwtpsfrns6lel97mfx5c3nqfe8fq791.png)
C.) 92
![80+100+85+92=357\\(357)/(4) =89.25](https://img.qammunity.org/2021/formulas/mathematics/middle-school/pclqo5jf9wligb4ogeu990jv5ak5f6riti.png)
D.) 95
![80+100+85+95=360\\(360)/(4) =90](https://img.qammunity.org/2021/formulas/mathematics/middle-school/wei06jlgkolbsnt27vbgw5vb59h77q314t.png)
The next score on the quiz needs to be 90 for the mean to be 90.