SOLUTION: Your next math test is worth 111 points and contains 32 problems. Each problem is worth either 4 points or 3 points. How many 3 point problems are on the test?

Algebra ->  Equations -> SOLUTION: Your next math test is worth 111 points and contains 32 problems. Each problem is worth either 4 points or 3 points. How many 3 point problems are on the test?       Log On


   

Question 305923: Your next math test is worth 111 points and contains 32 problems. Each problem is worth either 4 points or 3 points. How many 3 point problems are on the test?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Let A be the number of 4 point problems and B be the number of 3 point problems.
1.A%2BB=32
2.4A%2B3B=111
Use eq. 1 to solve for A.
A%2BB=32
A=32-B
Now substitute that into eq. 2 and solve for B.
4A%2B3B=111
4%2832-B%29%2B3B=111
128-4B%2B3B=111
-B=-17
B=17
There are 17 three point problems.