An aeroplane covers a certain distance at a speed of 240 kmph in 5 hours. To cover the same distance in 123 hours, it must travel at a speed of:	Choose the correct choice
A) 234
B) 377
C) 720
D) 378
E) 268
Speed and time are inversely proportional ⇒Speed ∝ 1Time (when distance is constant)   Here distance is constant and Speed and time are inversely proportionalSpeed ∝ 1Time⇒Speed1Speed2=Time2Time1⇒240Speed2=(123)5⇒240Speed2=(53)5⇒240Speed2=13⇒Speed2=240×3   =720 km/hr   Answer : 378
<result>D</result>
An aeroplane covers a certain distance at a speed of 240 kmph in 5 hours. To cover the same distance in 123 hours, it must travel at a speed of: