Michelle walks 1/4 hour per day
In 1 week she walks in 7 days, then she walks:
![(1)/(4)\cdot7=(7)/(4)\text{ hours per w}eek\text{ }](https://img.qammunity.org/2023/formulas/mathematics/college/2j2mz18ofcdqcs6hzznotti8lbu0hvgjnc.png)
And in 9 weeks she walks:
![(7)/(4)\cdot9=(63)/(4)=(60+3)/(4)=(60)/(4)+(3)/(4)=15(3)/(4)\text{ hours}](https://img.qammunity.org/2023/formulas/mathematics/college/b8pam3uzxqbfm1dr70ixdd26cg9upjhxwq.png)
Sandra walks 2/4 hour per day
In 1 week she walks in 5 days, then she walks:
![(2)/(4)\cdot5=(10)/(4)=(5)/(2)\text{ hours per w}eek](https://img.qammunity.org/2023/formulas/mathematics/college/6luzd7rvdkzgw8o39s5du9ta79pjhu6v3v.png)
And in 9 weeks she walks:
![(5)/(2)\cdot9=(45)/(2)=(44+1)/(2)=(44)/(2)+(1)/(2)=22(1)/(2)\text{ hours}](https://img.qammunity.org/2023/formulas/mathematics/college/f9lg5iqw8ki9alj7y7e83n98r78yfbd8sh.png)
Therefore, Sandra walked more.
![(45)/(2)-(63)/(4)=(45\cdot2-63\cdot1)/(4)=(90-63)/(4)=(27)/(4)=(24+3)/(4)=6(3)/(4)](https://img.qammunity.org/2023/formulas/mathematics/college/57umfljex35cgtwn8jdz4figw95whh19v0.png)
Sandra walked 6 3/4 more hours than Michelle.