Question: mp32q7 a man walks 70 km he walks x km...

(MP32Q7) A man walks 70 km. He walks x km at 8 km/h and y km at 10 km/h.
a) Find the length of time he was walking at 8 km/h in terms of x, and the length of
time he was walking at 10 km/h in terms of y.
b) Find his average speed in terms of x and y.
c) If the man walks at 10 km/h for the time he was walking at 8 km/h and at 8 km/h for
the time he was walking at 10 km/h, he walks 72 km. Find x and y.