NDA2019MathematicsSequences and SeriesActual

A car travels first 60 km at a speed of 3 v km / hr and travels next 60 km at 2 v km / hr . What is the average speed of the car?

Options

A2.5 vkm / hr
B2.4 vkm / hr
C2.2 vkm / hr
D2.1 vkm / hr

Correct answer

B. 2.4 vkm / hr

Step-by-step solution

For first 60 km , speed =3 v kmph for next 60 km speed =2 v kmph aligned & avg. speed = Total distance Total time & = 120 60 3 v + 60 v & = 2 1 3 v + 1 2 v & = 2 v 5 6 & = 12 v 5 =2.4 vkmph aligned

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