Consider the relation,
[tex]\text{Speed}=\frac{\text{ Distance}}{\text{ Time}}[/tex]The total time taken by Sarah for biking and jogging is 4 hours.
Given that her speed for biking was 10 mph, the time taken to bike 35 miles is calculated as,
[tex]\begin{gathered} T_b=\frac{35}{10} \\ T_b=3.5\text{ hours} \end{gathered}[/tex]So, out of the total 4 hours of exercise, Sarah spent 3.5 hours riding her bike.
The remaining 0.5 hour must have been spent on jogging,
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