For Ms Hurst:
Distance covered by her = Speed * time taken by her
Given:
Speed of Ms Hurst = 10miles/min
Time taken = 60 mins (since they both ran for 60minutes)
Substitute into the formula
Distance covered by Ms Hurst = 10mil/min * 60min
Distance covered by Ms Hurst = 600 miles
Hence Ms Hurst completed 600 miles