Question

Shawn's family car holds 16 gallons of fuel. Each day the car uses 0.8 gallons to get to school and back. A warning light comes on when there is less than 1.5 gallons left in the fuel tank. How many days can Shawn drive the car before the warning lights come on?

Answer 1

Given :

Shawn's family car holds 16 gallons of fuel.

Each day the car uses 0.8 gallons to get to school and back.

A warning light comes on when there is less than 1.5 gallons left in the fuel tank.

To Find :

How many days can Shawn drive the car before the warning lights come on.

Solution :

Let, after x days warning come.

So,

$16 - 0.8x < 1.5\\\\16-1.5<0.8x\\\\0.8x > 14.5\\\\x > \dfrac{14.5}{0.8}\\\\x > 18.125$

Therefore, at 19th day the warning light will start glowing.

Hence, this is the required solution.