In detail

An old riddle

An old riddle

At a Easter meal, they ate ten dozen eggs, one after the other, without pause. On the first plate they consumed 30 eggs at a rate of 3 eggs per minute, which took 10 minutes.

On the second plate they ate 30 eggs, 2 every minute, which took 15 minutes.

Finally, on the third plate they ate the 60 eggs that were left, at first 3 and then 2 per minute, alternately, making an average of 5 eggs every two minutes.

“Without you having to eat a lot of coconut with math,” said Dutch Frank, the barber who explained this problem to me "Tell me how long it would have taken to eat those ten dozen eggs if there had been half the guests in the meal."

Solution

Many fans were confused in at least two of the pitfalls of this version of this old puzzle.

When it is said that they needed 10 minutes to eat 30 eggs on the first plate, at a rate of 3 eggs per minute, and 15 more minutes to eat 30 more at a rate of two eggs per minute, this gives us 60 eggs in 25 minutes .

But during the third dish they ate 60 more eggs, first 3 per minute and then 2 per minute, thus making an average of 5 eggs every 2 minutes. And they make 60 eggs in 24 minutes. With that in total they ate the eggs of the three dishes in 49 minutes.

But the barber wanted to know how long it would take for half the guests who had eaten the eggs to eat. Mathematicians said that if the eggs were eaten in 49 minutes, half of the guests would have needed twice as much time, that is 98 minutes. It was our fans who discovered that the eggs, which should be small because they were eaten by only one person! It was a very exclusive meal of one person, so half of the guests could not have eaten any! Take the times you are given. 30 eggs in 10 minutes, then 30 in 15 and 60 in 24 and you will see that they only ate the eggs one after the other and, as you are told, they ate without pause, that is, a person is needed to do the job .

More than one must have realized that the last 60 eggs were eaten, first three per minute and then two per minute. How could two people eat three eggs? Or how could three people eat two?