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A car was driving at 60 Km/h for 20 minutes, and then at 90Km/h for an 11 Jul 2016, 12:32
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A car was driving at 60 Km/h for 20 minutes, and then at 90Km/h for another 40 minutes. What was its average speed?

A. 80.
B. 75.
C. 70.
D. 65.
E. 54.
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A car was driving at 60 Km/h for 20 minutes, and then at 90Km/h for an 11 Jul 2016, 14:11
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A. ( 60 * 1/3 + 90 * 2/3 ) / 1

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A car was driving at 60 Km/h for 20 minutes, and then at 90Km/h for an 12 Jul 2016, 00:12
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driving at 60 Km/h for 20 minutes ,distance covered = 60*1/3=20 km
driving at 90 km/h for 40 minutes ,distance covered = 90*2/3=60 km

average speed = total distance/total time = 80/1 = 80 km/h
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A car was driving at 60 Km/h for 20 minutes, and then at 90Km/h for an 13 Jul 2016, 07:37
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60*20/60 + 90*40/60
=20+60
=80
And:A
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A car was driving at 60 Km/h for 20 minutes, and then at 90Km/h for an 18 Jul 2016, 16:12
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The ratio of times traveled is 1:2 and time varies inversely with speed (2:1), then the weight of 90Km/h must be twice than that of 60Km/h .
Therefore, Option A. 80
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A car was driving at 60 Km/h for 20 minutes, and then at 90Km/h for an 18 Jul 2016, 19:19
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3 equal time segments @ 60,90,90 mph
(60+90+90)/3=80 mph average speed
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A car was driving at 60 Km/h for 20 minutes, and then at 90Km/h for an 26 Oct 2018, 07:53
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Bunuel
A car was driving at 60 Km/h for 20 minutes, and then at 90Km/h for another 40 minutes. What was its average speed?

A. 80.
B. 75.
C. 70.
D. 65.
E. 54.
Total Distance travelled is \(60*\frac{20}{60} + 90*\frac{40}{60}=80\)
Total Time taken is 20 min + 40 min = 60 Min = 1 Hour

So, Average speed is 80 km/hr ; Answer must be (A) 80
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A car was driving at 60 Km/h for 20 minutes, and then at 90Km/h for an 14 Jan 2025, 15:28
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