The number of students at Marita’s school decreased to 90% of last year’s number. Last year, there were 1,500 students. How many students are there this year?

1,350

Step-by-step explanation:

To solve this problem, we need to figure out what 90% of 1,500 is. We will need to multiply 1,500 by 90% to get our answer. Don't forget that we will also need to switch 90% to its decimal form (90% - > 0.9).

1,500 x 0.9 = 1,350

This means that there are 1,350 students at Marita's school.