Question

The fire department has seen an increase in smoke detector sales since 2015. In 2015,

they sold 350 detectors which is up from the previous year by 105%. How many did they
sell in the previous year?

Answer 1

Explanation:

Given the amount of detectors sold in the current year = 350

percent increment = 105%

To get the amount sold the previous year, we will use the expression;

(105% of x) + x = 350

1.05x = 350 + x

1.05x + x = 350

2.05x = 350

x = 350/2.05

x = 170.7

Hence the amount sold the previous year was 170.7 detectors