Answer:
90.6
Step-by-step explanation:
I think you have the first line incorrect. You show below that 10 students scored 90, so the first line is that 2 students scored 100, not 90. The line with the score of 90 is missing the number of students, but we can find it out. Call that number x for now.
Two students scored 100 each 2
x students scored 95 on each test x
ten students scored 90 on each test 10
three students score 80 on each test 3
and one student scored 70 <u> + 1 </u>
x + 16
There are x + 16 students accounted for. The total number of students is 25.
x + 16 = 25
x = 9
9 students scored 95 on each test.
Now add up all the points scored by all students.
Two students scored 100 each (2 * 90) 200
9 students scored 95 on each test (9 * 95) 855
ten students scored 90 on each test (10 * 90) 900
three students score 80 on each test (3 * 80) 240
and one student scored 70 (1 * 70) <u> + 70 </u>
Sum of all points: 2245
Now we find the average grade by dividing the sum of the points by the number of students.
average = sum/number = 2265/25 = 90.6
