Answer:
Sandra need to score at least <u>56%</u> in her fifth test so that her average is 80%.
Step-by-step explanation:
Given:
First 4 test scores = 87%, 92%, 76%,89%
Average targeted = 80%
We need to find the minimum score she needs to make on fifth test to achieve average of at least 80%.
Solution:
Let the minimum score she needs to make in fifth test be 'x'.
Total number of test = 5
Now we know that;
Average is equal to sum of all the scores in the test divided by number of test.
framing in equation form we get;
![\frac{87+92+76+89+x}{5}=80](https://tex.z-dn.net/?f=%5Cfrac%7B87%2B92%2B76%2B89%2Bx%7D%7B5%7D%3D80)
Multiplying both side by 5 we get;
![\frac{344+x}{5}\times 5=80\times 5\\\\344+x=400](https://tex.z-dn.net/?f=%5Cfrac%7B344%2Bx%7D%7B5%7D%5Ctimes%205%3D80%5Ctimes%205%5C%5C%5C%5C344%2Bx%3D400)
Subtracting both side by 344 we get;
![344+x-344=400-344\\\\x=56\%](https://tex.z-dn.net/?f=344%2Bx-344%3D400-344%5C%5C%5C%5Cx%3D56%5C%25)
Hence Sandra need to score at least <u>56%</u> in her fifth test so that her average is 80%.
Answer:
I believe the answer is D.
Hope i'm right
Step-by-step explanation:
Answer: p=9
explanation: 6 reds + 3 blues = 9.