Question

Meg started her trip with 11 1/2 gallons of gas in her car's tank. She bought an additional 6 4/5 gallons on her trip and arrived back home with 3 3/10 gallons left. How much gas did she use on the trip?

Answer 1

Meg used 15 gallons. First you find the  lowest common denominator to add 11 1/2 and 6 4/5, which is 10. What you do to the bottom you have to do to the top. You multiply 2 and 5, which gives you 10. 1 times 5 is 5... 11 5/10. 2 times 5 is 10, 4 times 2 is 8... 6 8/10. Add 11 5/10 and 6 8/10 and it gives you 18 3/10. To find out how much she used subtract the total amount she bought and how much she returned home with. The fractions cancel out since 3/10 minus 3/10 equals 0. You're just left with 18 minus 3, which is 15.

Answer 2

Answer:

Hence, the amount of gas she used on the trip is:

15 gallons.

Step-by-step explanation:

Meg started her trip with 11 1/2 gallons of gas in her car's tank.

i.e. we can represent the mixed fraction 11 1/2 in fraction as:

$11\frac{1}{2}=\dfrac{23}{2}gallons$

She bought an additional 6 4/5 gallons on her trip.

i.e. we can represent the mixed fraction 6 4/5 in fraction as:

$6\frac{4}{5}=\dfrac{34}{5}gallons$

Hence, the amount of gas filled in tank:

$=\dfrac{23}{2}+\dfrac{34}{5}\\\\=\dfrac{23\times 5+34\times 2}{10}\\\\=\dfrac{115+68}{10}\\\\=\dfrac{183}{10}gallons$

now after coming back home the amount of gas left in the car tank is:

3 3/10 gallons ; which could be represented in fraction as:

$3\frac{3}{10}=\dfrac{33}{10}$

Amount of gas used in the trip is:

=Amount of gas filled-gas remaining

$=\dfrac{183}{10}-\dfrac{33}{10}\\\\=\dfrac{183-33}{10}\\\\=\dfrac{150}{10}\\\\=15gallons$

Hence, the amount of gas she used on the trip is:

15 gallons.