Question
A boy goes to school with a speed of 50 km/h and comes
back with a speed of 30 km/h. find his average speed?Solution
Since the distance travelled by a boy (going to school and coming back from school) is equal. So, average speed = 2xy/(x + y) Average speed = (2 x 50 x 30)/(50 + 30) Average speed = (2 x 50 x 30)/80 = 37.5 km/hr
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