Question

The number of students at a school decreased 20% from 2010 to 2011. If the number of

students enrolled in 2011 was k, which of the following expresses the number of students enrolled in 2010
in terms of k?
A) 0.75k
B) 1.20%
C) 1.25K
D) 1.5k​

Answer 1

C

Explanation:

Okay, here we have a reduction in the number of students by 20% from 2010 to 2011.

In 2011, we had k students, so we want to calculate the number of students we had in 2010.

Let the number of students present in 2010 be x

So mathematically;

x - 20% of x = k

x - 0.2(x) = k

0.8x = k

x = k/0.8

x = k * 1/0.8

x = k * 1.25

x = 1.25k