SOLUTION: Between Brisbane and Toowoomba workers are repairing a section of road 7.5 kilometres in length. The speed limit on this section of the road is usually 100 km/h. Due to the roadw

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Question 1114002: Between Brisbane and Toowoomba workers are repairing a section of road 7.5
kilometres in length. The speed limit on this section of the road is usually 100 km/h. Due
to the roadwork, the speed has been reduced to 60 km/h. How many minutes will the
roadwork add to the journey?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Between Brisbane and Toowoomba workers are repairing a section of road 7.5
kilometres in length.
The speed limit on this section of the road is usually 100 km/h.
Due to the roadwork, the speed has been reduced to 60 km/h.
How many minutes will the roadwork add to the journey?
:
time = dist/speed
:
Find how long it takes to go 7.5 km at 100 km/h
t = 7.5%2F100 = .075 hrs, which is 60*.075 = 4.5 min
Find how long it takes to go 7.5 km at 60 km/h
t = 7.5%2F60 = .125 hr which is 60*.125 = 7.5 min
therefore
7.5 - 4.5 = 3 min longer