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
[tex]40x = 65*50[/tex]
[tex]x = \frac{65*50}{40}[/tex]
[tex]x = 81.25[/tex]
He should drive his car at a speed of 81.25 kilometers per hour.
