Question

A car travels at 55 mi/h and gets 11km/l of gasoline. How many gallons of gasoline are needed for a 3.0-h trip?

Answer 1

Answer:

6.377 gallons of gasoline are needed for the 3h trip.

Step-by-step explanation:

This problem can be solved by consecutive direct rule of three's.

A rule of three is called direct when the relationship between both measures is direct. It means that as the value one of measures increases, so will the alue of the other measure.

The first step is to know how much the car traveled.

The trip was 3-h long, and the car traveled at 55 mi and hour. So:

1 hour - 55mi

3 hour - x mi

x = 55*3

x = 165 miles

The car traveled 165 miles.

Then we need to know how many kilometers the car traveled.

Each mile has 1.61km, so:

1 mile - 1.61km

165 miles - x km

x = 165*1.61

x = 265.5 km

The car traveled 265.5 km

Now we need to know how many liters the car used

For each liter used, the car can travel 11 km, so:

1L - 11km

xL - 265.5 km

11x = 265.5

$x = \frac{265.5}{11}$

x = 24.14L

The car used 24.14L

The final step is converting from L to gallons.

Each liter has 0.264 gallons, so:

1L - 0.264 gallons

24.14L - x gallons

x = 0.264*24.14

x = 6.377 gallons

6.377 gallons of gasoline are needed for the 3h trip.