Joe averaged 80km/h for 3.2 hours, and then he slowed to 70km/h for 1.5 hours: a. how far did he drive in all. b. what was his average speed for the entire trip to the nearest tenth?
2006-11-28 12:00:31 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
First, find out how far Joe travelled:
80 km/hr * 3.2 hours + 70 km/hr * 1.5 hr=
256 km + 105 km = 361 km
It took a total of 4.7 hrs to travel 361 km.
The average speed is 391 km / 4.7 hr = 76.8 km / hr
2006-11-28 12:06:27 · answer #1 · answered by hokiejthweatt 3 · 0⤊ 0⤋
Rate x Time = distance so...
a) 80 (3.2) + 70 (1.5) = 256 + 105 = 361 km
b) 361 km/4.7 hr = 76.81 kph (rounded value)
2006-11-28 20:08:39 · answer #2 · answered by Eds 7 · 0⤊ 0⤋
Distance = Rate * Time
D = 80(3.2) + 70(1.5) = 256 + 105 = 361
D = R*T
R = D/T
R = 361/(3.2 + 1.5) = 361/4.7 = 76.8
2006-11-28 20:10:43 · answer #3 · answered by kindricko 7 · 0⤊ 0⤋
Distance = speed times time
2006-11-28 20:06:50 · answer #4 · answered by hayharbr 7 · 0⤊ 0⤋
Distance=speed*time
So 80km/h * 3.2h = 256km
70km/h*1.5H = 105km
add both = 361.0km
2006-11-28 20:09:01 · answer #5 · answered by af12af3af 2 · 0⤊ 0⤋