Answer:
[tex]30\ miles[/tex]
Step-by-step explanation:
First convert mixed number to an improper fractions
[tex]1\frac{7}{8}=\frac{1*8+7}{8}=\frac{15}{8} \ gallons[/tex]
[tex]56\frac{1}{4}=\frac{56*4+1}{4}=\frac{225}{4} \ miles[/tex]
By proportion
[tex]\frac{(225/4)}{(15/8)}\frac{miles}{gallons} =\frac{x}{1}\frac{miles}{gallon} \\ \\x=(225*8)/(4*15)\\ \\x= 30\ miles[/tex]
