Answer:
You would need to score a 93% to have an average of 90.
Step-by-step explanation:
Well, to check my work you would need to find the average.
So, 93 + 92 + 88 + 87 = 360. Then you divide by four; 360 / 4 = 90. ^^
The awnser is the simplified stystem is the arbitrary solution of the original system of equations
Round down to 10. 13 goes to 10.