Answer :
Answer:
100
Step-by-step explanation:
After five test, Allison's average score was 88. Let the total of her score be x
x/5=88
Cross multiply
x=88(5)
x=440
The total scores of the five test was 440.
After the sixth test, her acreage score became 90. Let the total score again be x
x/6=90
Cross multiply
x=90(6)
x=540
The sixth score is 540-440=100
Answer:
Sixth test was 100
Step-by-step explanation:
5 tests average is 88 - An equation for the average is...
5x/5 = 88 (where x is 88) so it can also be 440/5 = 88 and this is correct
The sixth test has to be greater than 88 as the average increases; an equasion for this is...
Let y = the sixth test result
Let x = the previous average; 88
(5x + y)/6 = 90 (the new average)
5x + y = 540
As said before 5x = 440 so we can substitude 440 into 5x
440 + y = 540 (-440)
y = 100
So, the equation shows that the 6th test result is 100 but we should check to see if this is correct so...
440 + 100 = 540
540 / 6 = 90 (so we are correct!)