A robber is in a fast car, hurrying away from the scene of his crime. His car can go at 150 km/h. He will be safe if he can reach the border, 40km away. A police car arrives at the scene of the crime. The police are late! The robber has already travelled 10 km towards the border. The police car set off in hot pursuit. Question: calculate how long it will take the robber to reach the border.
Question 2: How fast must the police car travel if it is to catch the robber before he reaches the border ?

If someone do I will make her or him brainliest.

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ardni313 ardni313 · Answer 1 · 2021-01-13T08:53:12+01:00

1. time taken by the robber = 0.2 h

2. speed of the police's car = 200 km/h

Given

Speed of a robber's car = 150 km/h

Distance to border = 40 km

Required

1. time to reach border

2. speed of police's car

Solution

1. The robber has already travelled 10 km

Distance remains = 30 km

Time to reach = distance : speed = 30 km : 150 km/h = 0.2 h

2. time taken by robbers = time taken by police

distance needed by the police = 40 km

0.2 h = distance : speed

0.2 h = 40 km : speed

speed = 40 km : 0.2 = 200 km/h