Question

3.) AI 65 kom hr. Alfred can reach home in 50 minutes. At what speed should he drive his car

Answer 1

Answer:

He should drive his car at a speed of 81.25 kilometers per hour.

Step-by-step explanation:

With a velocity of 65 kilometers per hour, he reaches home in 50 minutes. What speed he needs to reach home 10 minutes earlier, that is, in 50 - 10 = 40 minutes?

To solve this, we use the relation between inverse proportion variables(as the velocity increases, time needed decreases), that is, a rule of three with line multiplication, instead of cross. So

65 kilometers per hour - 50 minutes

x kilometers per hour - 40 minutes

So

$40x = 65*50$

$x = \frac{65*50}{40}$

$x = 81.25$

He should drive his car at a speed of 81.25 kilometers per hour.