Question

Mr. Tang gives a math test worth 90 points that contain 25 questions. Multiple-choice questions are worth 3 points and word problems are worth 4 points. How many of each type of question are there?

Answer 1

m=10

w=15

Explanation:

m + w = 25

3m + 4w = 90

Let's do substitution, first by solving the first equation for m.

m = 25 - w

Substitute!

3(25 - w) + 4w = 90

75 - 3w + 4w = 90

w = 15

m = 25 - 15 = 10