Question

If a person travel at speed of 40 km/hr and 60 km/hr, he will reach office at 7PM and 2PM respectively. If he wants to reach office at 5PM at what speed should he travel?

Answer 1

Answer:

55 milles per hower

Step-by-step explanation:

Answer 2

Step-by-step explanation:

S1=40 km/hr

S2=60 km/hr,

let d be the distance travelled by person

we know d/s=time

total time taken to reach the office =5hrs

$\frac{d}{40} - \frac{d}{60} = 5 \\ \\ d(\frac{3 - 2}{120} ) = 5 \\ d = 600km$

to reach for 2hrs

speed of the person=

$\frac{600}{2} = 300km \: per \: hr$

He should travel with speed of 309km per hr