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Question 150148: This problem is from a test. I have the solution, but I am unsure of where one of the numbers came from, so I would not be able to do a similiar problem on the final.
The class average on a math test was 82 out 100. The girls in the class scored 966 points. How many total points did the 8 boys score?
The solution I have looks like this:
966 + b/19 = 82
966 + b = 1558 (where does the 1558 come from?)
b = 592: This problem is from a test. I have the solution, but I am unsure of where one of the numbers came from, so I would not be able to do a similiar problem on the final.
The class average on a math test was 82 out 100. The girls in the class scored 966 points. How many total points did the 8 boys score?
The solution I have looks like this:
966 + b/19 = 82
966 + b = 1558 (where does the 1558 come from?)
b = 592
Answer by vleith(1238) About Me  (Show Source):
You can put this solution on YOUR website!
Your problem did not state how many students were in the class. But your first line in the solution uses the number 19. So I will assume there are 19 students.
You are told the class average is 82, that girls total was 966 and that 8 boys took the test.
So, the total points scored on the test is:
Total= girlsTotal + boysTotal
Total = 966 + 8*boysAverage
You also know the class average was 82. So the Total= 19*82 = 1558
Substitute the total and solve for boysAverage
Total = 966 + 8*boysAverage
1558 = 966 + 8*boysAverage
1558-966 = 8*boysAverage
592 = 8*boysAverage
74 = boysAverage