Question

A car's fuel economy is 30 mpg. a warning light is displayed if the remaining distance that can be driven before the car runs out of gas drops below 50 miles. initially the car has 10 gallons of gas. how many gallons, g, can be used before the warning light comes on?

Answer 1

So 10 gallons of gas would let you travel 300 Miles. 

x gallons = 50 Miles

10 : 300 :: x : 50 

x = 500/300

x = 1.66667 gallons. 

So, the car would run 10 - 1.6666 gallons = 8.33 gallons.

After that, the warning light turns ON! 

Hope this helps!!

Answer 2

Answer:

8.33 gallons

Explanation:

Given: A car's fuel economy is 30 mpg. a warning light is displayed if the remaining distance that can be driven before the car runs out of gas drops below 50 miles.

To Find: initially the car has 10 gallons of gas. how many gallons, g, can be used before the warning light comes on.

Solution:

Total fuel in car$=10\text{g}$

fuel economy of car $=30\text{mpg}$

fuel required to ride 30 mile $=1\text{g}$

fuel required to ride 1 mile $=\frac{1}{30}\text{g}$

Now,

Fuel required to ride 50 miles $=50\times\frac{1}{30}\text{g}=\frac{5}{3}\text{g}$

fuel left in car when warning light is displayed $=\text{Fuel required to ride 50 miles left}$

                                                                        $=\frac{5}{3}\text{g}$

Amount of fuel that can be consumed before warning light dislays

$\text{Total fuel}-\text{fuel left when warning light displays}$

            $10-\frac{5}{3}$

            $\frac{25}{3}\text{g}$        

            $8.33\text{g}$

8.33 gallons fuel can be used before warning light comes on