If Roger ran 5 miles in 150 minutes, Ryan ran 10 miles in 300 miles, and Rick ran 5 miles in 2 and ½ hours, who had the best rate of running(fastest time)?

All three have same rate of running.

Step-by-step explanation:

Given that:

Distance covered by Roger = 150 minutes

Time taken by Roger = 5 miles

Distance covered by Ryan = 300 minutes

Time taken by Ryan = 10 miles

Distance covered by Rick = 2 hours

Time taken by Rick = 2 miles

To find:

Who has the fastest rate of running?

Solution:

First of all, we need to convert the time in hours and then we need to apply the formula for relation between Speed, time and distance.

Then we can compare the Speed.

60 minutes = 1 hour

150 minutes =

300 minutes = 5 hours

Formula for Speed:

Rate of running (speed) of Roger = = 2 miles/hr

Rate of running (speed) of Ryan = = 2 miles/hr

Rate of running (speed) of Rick = = 2 miles/hr

Therefore, All three have same rate of running.

25 : 1

Step-by-step explanation:

The diameter of the football is 5 times the diameter of the cricket ball. This means that the radius of the football is also 5 times the radius of the cricket ball.

Let the radius of the football be R.

Let the radius of the cricket ball be r.

This implies that:

R = 5r

Both balls are spherical.

The surface area of the cricket ball is given as:

The surface area of the football is given as:

Therefore, the ratio of their surface areas is:

A : a

= 100 : 4

25 : 1