Answer:
time = 70 minutes
Explanation:
According to the question the whole race is 10 kilometer. It takes her 17. 5 minutes to cover a distance of 2.5 km.
The rate the runner used to cover the distance of 2.5 km can be computed as follows:
rate = distance / time
distance = 2.5 km
time = 17.5 minutes
rate = 2.5/17.5
rate = 0.14285714285 kilometer/minutes
rate = 0.14285714285 km/min
Use the rate to calculate for the time the runner used for the whole distance of 10 km
rate = distance/time
rate = 0.14285714285 km/min
distance = 10 km
rate = distance/time
cross multiply
time = distance/rate
time = 10/0.14285714285
time = 70 minutes
time = 70 minutes