Taxis leave station `X` for station `Y` every `10 min`. Simultaneously, a taxi also leaves station `Y` for station`X` every `10 min`. The taxis move at the same constant speed and go from `X` and `Y` or vice-versa in `2 h`, How many taxis coming from the other side will meet each taxi enroute from `Y` and `X`?.

Options

A. (a) ` 11`
B. (b) `12`
C. (c ) ` 23`
D. (d) `24`

Answer

C

Explanation

No. of taxies leaving a station (A) in (2) hours ` = 2 xx 60 /10 = 12 `. Therefore a taxi standing at a location (B), will encounier ` 12 1 taxies in `2` hours. If taxi leaves station (B) and moves towards (A) will be meeting (11) more taxies enroute and it will be meeting the twelfth taxi at the location of (a) which is just going to start. Therefore this taxi is not counited in the total no. of taxies enroute . Thus the total no. of taxies encountered enroute ,brgt `12 + 11 23`.