Question

The 7th grade class experienced a 15% decrease in enrollment. Last year, the 7th grade class had 280 students. How many students are enrolled in the 7th grade class this year?

Answer 1

238 students are enrolled in the 7th grade class this year

Solution:  

Given that

Percentage decrease in number of students enrolled in 7th grade = 15%

Number of students enrolled last year = 280  

Need to determine number of students enrolled in 7th grade this year.

Lets assume number of students enrolled this year = x  

Percentage decrease in enrollment = (Number of student enrolled last year – Number of students enrolled this year) whole divided by number of students enrolled last year multiplied by 100

$\begin{array}{l}{\Rightarrow 15=\frac{280-x}{280} \times 100} \\\\ {=>15 \times 280=28000-100 x} \\\\ {=>100 \mathrm{x}=28000-4200=23800} \\\\ {\Rightarrow x=\frac{23800}{100}} \\\\ {\Rightarrow x=238}\end{array}$

Hence number of students enrolled this year = 238.