SOLUTION: a math test has 25 problems. Some problems are worth 2 points and some are worth 3 points and the total for the test is 66. How many 2 points and 3 points promblems are there.

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Question 858961: a math test has 25 problems. Some problems are worth 2 points and some are worth 3 points and the total for the test is 66. How many 2 points and 3 points promblems are there.
Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
x+y=25
2x+3y=66

2x+3(25-x)=66
2x+75-3x=66
75-66=x
x=9
y=25-9=16
there are 9 - 2pt problems and 16 - 3pt problems