Sagot :
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:
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:
[tex]11\frac{1}{2}=\dfrac{23}{2}gallons[/tex]
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:
[tex]6\frac{4}{5}=\dfrac{34}{5}gallons[/tex]
Hence, the amount of gas filled in tank:
[tex]=\dfrac{23}{2}+\dfrac{34}{5}\\\\=\dfrac{23\times 5+34\times 2}{10}\\\\=\dfrac{115+68}{10}\\\\=\dfrac{183}{10}gallons[/tex]
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:
[tex]3\frac{3}{10}=\dfrac{33}{10}[/tex]
Amount of gas used in the trip is:
=Amount of gas filled-gas remaining
[tex]=\dfrac{183}{10}-\dfrac{33}{10}\\\\=\dfrac{183-33}{10}\\\\=\dfrac{150}{10}\\\\=15gallons[/tex]
Hence, the amount of gas she used on the trip is:
15 gallons.