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4 years ago

14

You plan a car trip for which you want to average 90 km/h. You cover the first half of the distance at an average speed of only

48 km/h. What must your average speed be in the second half of the trip to meet your goal?

1 answer:

xz_007 [3.2K]4 years ago

7 0

T1=S/V1T2=Ttot-T1=(2S/Vtot)-S/V1V2=S/T2 = S / (2S/Vtot-S/V1)Simplify in V2 = V1Vtot/(2V1-Vtot) = 48 * 90 / 6 = 720 km/hr

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