Answer:
There are 5 multiple choice questions
Step-by-step explanation:
Let
m ----> the number of multiple choice in a test
s ----> the number of short answer in a test
we know that
The test has 20 questions
so
[tex]m+s=20[/tex] ----> equation A
A test is worth 50 points
so
[tex](1)m+3(s)=50[/tex]
[tex]m+3s=50[/tex] ----> equation B
Subtract equation A from equation B
[tex]m+3s=50\\-m-s=-20\\-------\\3s-s=50-20\\2s=30\\s=15[/tex]
Find the value of m
[tex]m+s=20\\m+15=20\\m=5[/tex]
therefore
There are 5 multiple choice questions
