Question

Monique randomly surveyed 30 students from

her class and found that 18 had a dog or a cat for a
pet. If there are 870 students in Monique's school,
predict the total number of students with a dog or a
cat.

Answer 1

522

Explanation:

Find the percent of students in her class that have a dog or cat:

1. Set up a proportion:
   `(18)/(30) = (x)/(100)`
2. Cross multiply, then divide: 18 × 100 = 1800, 1800 ÷ 30 = 60
3. So, 60% have a dog or cat

Find 60% of the total amount of students in Monique's school:

1. 60% of 870 =
   `(60)/(100)` ×
   `(870)/(1)`
2. 
   `(60)/(100)` ×
   `(870)/(1) = (52200)/(100)`
3. 
   `(52200)/(100) = (522)/(1) = 522`

I hope this helps!