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A person went from A to B at an average speed of x km/hr and returned from B to A at an average speed of y km/hr. What was his average speed during the total journey ?
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x + y 2xy -
2xy x + y -
2 x + y -
1 + 1 x y
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Correct Option: B
| Required average speed = |  |  | kmph | |
| x + y |
[Since, can be given as corollary If the distance between A and B be z units, then
| Average speed = | |
| Time taken |
| = | |||||
| + | |||||
| x | y | ||||
| = | |||||
| + | |||||
| x | y | ||||
| = | |||||
| xy | |||||
| = | |
| x + y |
