Answer:there are 10 Multiple choice problems.
There are 5 open ended problems.
Explanation:
Let x represent the number of Multiple choice problems in the test.
Let y represent the number of open ended problems in the test.
Your your math test has 15 problems. . This means that
x + y = 15
Multiple choice problems are worth four points each and open ended problems are 12 points each. The maximum number of points possible on the test is 100. This means that
4x + 12y = 100- - - - - - - - - - 1
Substituting x = 15 - y into equation 1, it becomes
4(15 - y) + 12y = 100
60 - 4y + 12y = 100
- 4y + 12y = 100 - 60
8y = 40
y = 40/8 = 5
Substituting y = 5 into x = 15 - y, it becomes
x = 15 - 5 = 10