I don't know if I ever told you about the super-dog incident.
superdog can run extremely fast and increase his speed in an instant.
I have a wooden spoon and a rusty can, every time I hit the can with the spoon, it makes a “cling” sound that drives superdog nuts.
Each time he hears the "cling" sound he doubles his speed in an instant.

My friend has a dog also. One day we take our dogs to a circular race track which is exactly a mile long.

My friend’s dog does two laps of the track at a constant speed of 60mph.

Now it is superdog’s turn to do two laps of the track. Wanting to show off his unusual powers, superdog runs the first lap at 30mph. What is the MINIMUM number of times that I need to hit the can to ensure that superdog beats the other dog’s average speed of 60mph for the two laps?

(…and what is the probability that the other dog is a male?)

If superdog could run the second lap in 0 sec., then his average speed
for the two laps would be 60 mph. If it took him any amount of
time more than that, then his average speed would be more than 60 mph.

The probability of superdog losing this race: 100%.

Spoilsport!

??? isn't the whole point of this section to post problems and then solutions?

Well, yes. But I spent longer typing that one than it took stanalger to solve it and post his reply!

..but then I did say it was easy!

I thought it was clever ,I would never have got it.