Answer:
6 multiple choice questions and 22 open/extended response questions
Step-by-step explanation:
Let x be the number of multiple choice questions
Let y be the number of open response questions
Thus, we have a system of equations:
2x+4y=100
x+y=28
Solve bottom equation for desired variable, then plug in to top one:
x+y=28
x=28-y
2(28-y)+4y=100
56-2y+4y=100
56+2y=100
2y=44
y=22
Plug y back into bottom equation to get x:
x+22=28
x=6
So there are 6 multiple choice questions and 22 open/extended response questions.