Question

After 1 year, the value of a car decreases by 19%. The car is now worth £3078. What was the value of the car originally?​

Answer 1

3800

Explanation:

Variables:

O - Original cost

N - New cost

c - change factor

Step 1:

Recognize that if something decreases by 19%, it is worth 19% less

This means that the new price, fractionally, is 100% - 19% = 81%

So we can use c as 0.81 (81/100)

Step 2:

Write an equation to represent what is happening

N = O * c

Step 3:

Sub in what we know

3078 = O * 0.81

Step 4:

Rearange and solve

O = 3078 / 0.81 = 3800