Two motorists start together to travel to a certain destination, one at the speed of 4 km/h and the other at the speed of 6 km/h. Find the distance travelled by them (in km) if the motorist travelling at 4 km/h arrives half an hour after the other motorist.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 6.
Distance = Speed × Time
Let the distance covered by motorists be D km.
According to the given question,
Distance covered by motorist 1, D = 4T
And distance covered by motorist 2, D = 6(T - 0.5)
Equating the values of D,
⇒ 4T = 6(T - 0.5)
⇒ 4T = 6T - 3
⇒ 2T = 3
⇒ T = 1.5
Now, putting the value of T,
⇒ D = 4 × 1.5
⇒ D = 6 km
Hence the distance covered by the motorists is 6 km.