Question

A and B are 20 km apart we can walk at an average speed of 4 km per hour and B at 6 km per hour if they start working together each other at 7 p.m. then they will meet
a 8 am
b 8 30 am
c 9 am

Answer 1

$\frac{x}{4} = \frac{20 - x}{6} \\ 6x = 80 - 4x \\ 10x = 80 \\ x = 8$
9 pm will be answer

Answer 2

Answer:since the relative speed of A and B=6+4=10kmph

Therefore,time=20/10=2hours.

Therefore, they will meet at 9:00 am

Step-by-step explanation: