Answer:
55.50 miles/hour
Explanation:
time for ceremony = 25 minutes
church miles away = 11 miles
distance x
velocity v
time t
x=v*t
first 15 minutes:
x = 7 miles/h * 15 min
1 hour = 60 min
t1 = 15 min
t1= 1 hour * 15 min/60 min
t1= 0.25 hour
x = 7 miles/h * 0.25 h
x= 1.75 miles
miles left to church = 11 - 1.75= 9.25 miles
rest of the trip:
x = v*t
v=x/t
v =9.25 miles/ (25 min-15 min) = 9.25 miles/10 min
t2 = 10 min
t2 = 1 hour * 10 min/60 min
t2 = 1/6 hour
v = 9.25 miles / (1/6) hour=9.25 *6 miles/hour = 55.50 miles/hour