MATH SOLVE

2 months ago

Q:
# a math test is worth 100 points and has 30 problems. each problem is worth either 3 points or 4 points. how many 4- point problems are there?

Accepted Solution

A:

Let x = 3 point questions and y = 4 point questions.x + y = 30 total questionsRewrite as x = 30 - y3x + 4y = 100 total pointsreplace x in the points equation:3(30-y) +4y = 100Use distributive property:90 - 3y + 4y = 100Combine like terms:90 + y = 100Subtract 90 from both sides:y = 10There are 10 4 point questions.