A math test is worth 100 points and has 38 problems. Each problem is worth either 5 points or 2 points. How many problems of each points value are on the test
Accepted Solution
A:
Let x be the number of 5 points question. Let y be the number of 2 points question.
Total number of questions is 38 x + y = 38Β
Total points is 100 5x + 2y = 100
x + y = 38 ------------- (1) 5x + 2y = 100 ---------(2)
From (1): x + y = 38 x = 38 - y -------------- sub into (2) 5(38 - y) + 2y = 100 190 - 5y + 2y = 100 3y = 90 y = 30 ------------------ sub into (1) x + 30 = 38 x = 38 - 30 x = 8
There are 8 5-point questions and 30 2-point questions