Mr Jone's home distance is 60 miles away from his appointment place .
Distance = Speed x Time
Distance planned & distance covered is same.
Time covered is 20 minutes more than time planned ; Actual Speed is 15mph lower than planned speed (60 mph) , ie = 45 mph.
Let the planned time be = t , Actual time = t + 20 mints = t + 20 / 60 = t + 1/3 = 4 t / 3
As distance is same : 60 t = 45 ( 4t / 3)
60t = 60t
t = 1 hour
Distance = Speed x Time :
60 x 1 = 45 ( 4/3) = 60 miles
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