80 times 1 divided by 10 is 8.
ΔABC ~ ΔADE
AC/AE = AB/AD
AC/(AC+15) = 8/18
18AC = 8(AC+15)
18AC = 8AC + 120
18AC - 8AC = 120
10AC = 120
AC = 120/10
AC = 12
Answer:
93
Step-by-step explanation:
The mean of a list of numbers is the sum of the numbers divided by the count of the numbers in the list.
In this case, representing the eighth score with x, the mean is (611+x)/8
Solving for the mean:
88=(611+x)/8
Multiply both sides by 8
8*88=611+x
704=611+x
704-611=x
x=93
