You are driving home from school steadily at 95 km/h for 130 km. It then begins to reain and you slow to 65 km/h. You arrive home after driving 3 hours and 20 minutes.
a. How far is your hometown from school?
b. what was your average speed?
any advice is appreciated! thanks in advance!
2 Answers
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First. (130km) / (95km/h) = 1.37h
(first part of the trip) 1.37h x 95 km/h = 130km ( this double checks it)
(make sure you change 3 hr 20 to 3.34 to match units up)
3.34h – 1.37h = 1.97h
1.97h x 65 km/h = 128km
A) total distance 130km + 128 = 258km (2.6km x10^2)
B) 260/3.34h = 78km/h
(watch your sig figs)
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