Q.steve gets on the elevator at the 11th floor of a building and rides up at a rate of 57 floors per min. At the same time, joyce gets on an elevator on the 51st floor of the same building and rides down at a rate of 63 floors per min. If they continue travelling at the rates, then at which floor will their paths cross?
a)19 b)28 3)30 4)32
sol: divide the rate with common divisible number
here for 57 and 63 we can divide by 3, then 57/3=19 and 63/3=21
now add with floor i.e., 11+19=30(up) and 51-21=30(down)