SOLUTION: The first five figure skating judges gave Dora scores of 7.2, 7.3, 7.7, 7.8, and 7.5. What score does she need from the sixth judge to score a 7.55 average?

Algebra ->  sets and operations -> SOLUTION: The first five figure skating judges gave Dora scores of 7.2, 7.3, 7.7, 7.8, and 7.5. What score does she need from the sixth judge to score a 7.55 average?       Log On


   

Question 102434: The first five figure skating judges gave Dora scores of 7.2, 7.3, 7.7, 7.8, and 7.5. What score does she need from the sixth judge to score a 7.55 average?
Answer by doukungfoo(195) About Me  (Show Source):
You can put this solution on YOUR website!
To find the average of six numbers you need to add them together and divide by six. This problem tells us five of the the numbers and we need to figure out the sixth number so the resulting average will be 7.55.
So first lets add the five scores we are given:
7.2 + 7.3 + 7.7 + 7.8 + 7.5 = 37.5
Lets call the sixth score x and write an equation based on the given information.
%2837.5%2Bx%29%2F6=7.55
now we can solve for x
first multiply both sides by 6
6%28%2837.5%2Bx%29%2F6%29=7.55%2A6
37.5%2Bx=45.3
next subtract 37.5 from both sides
37.5-37.5%2Bx=45.3-37.5
x=7.8
Answer: Dora needs a 7.8 from the sixth judge