[tex]\text{Answer: }1\frac{23}{40}\ miles\text{ far she live from school.}[/tex]
Explanation:
Since we have given that
Speed at which Eugene walked all the way to school = 3 mph
After realizing that she forgot her math book, she ran back
Speed at which Eugene walked back to her house = 7 mph
Let the distance between her house and her school be x
According to question,
[tex]\frac{x}{3}+\frac{x}{7}=\frac{45}{60}\\\\\frac{7x+3x}{21}=\frac{3}{4}\\\\\frac{10x}{21}=\frac{3}{4}\\\\x=\frac{3\times 63}{4\times 10}=\frac{63}{40}=1\frac{23}{40}\ miles.[/tex]
Hence,
[tex]1\frac{23}{40}\ miles\text{ far she live from school.}[/tex]
