How to solve a percent word math problem in algebra

A middle school has 1200 students. Of these, 25% are in the eighth grade. Yesterday, 95% of all eighth graders were present. How many eighth-grade students were absent yesterday?

Solution

First, we need to find the total number of eighth grade students at this school.

25% of 1200 = 25% x 1200 = (25/100) x 1200 = 25 x 12 = 300 students

Next, we need to find how many eighth-grade students were present yesterday.

95% of 300 = 95% x 300 = 95 x 3 = 285 students.

Finally, we can find how many eighth graders were absent yesterday, by subtracting from the total number of eighth-grade students the number of students who were present yesterday.

300 – 285 = 15 students

Final answer: 15 eighth-grade students were absent yesterday