Question

The enrolment in a school this year is 552. This is an increase of 15% over last year's
enrolment. How many were enrolled last year?

Answer 1

find 12 × 60 using distribution property.

Answer 2

Answer:

If 552 is the enrolment in a school this year and that means a 15% increase over last year, then 480 were enrolled last year.

Step-by-step explanation:

Let Y be the number of students enrolled last year

Given

Enrolment in the school this year = 552

Increase in the percentage of enrolment from last year = 15%

Percentage increase = [( enrolment this year- enrolment last year)/enrolment last year ]*100

That is,

$15=\frac{552-Y}{Y}*100\\15Y=(552-Y)*100\\\frac{15Y}{100} =552-Y\\\\\frac{3Y}{20} +Y = 552\\\\\frac{3Y+20Y}{20} =552\\\\23Y=552*20\\\\Y=\frac{552*20}{23} \\\\=24*20\\\\=480$

So, 480 students were enrolled last year.