Question

Use a system of linear equations with two variables and two equations to solve.

175 students enrolled in a freshman-level chemistry class. By the end of the semester, 4 times the number of students passed as failed. Find the number of students who passed, and the number of students who failed.

Answer 1

35 failed and 140 passed

Explanation:

Let p = number who passed

f = number who failed

p+f = 175

4 times the number of students passed as failed, so we need to balance this to set it equal

4f = p

Substitute this into the first equation

4r+f = 175

5f = 175

5f/5 =175/5

f = 35

Now find the number who passed

p = 4f

p = 4*35

p =140