Riddles
It's been around for a thousands of years but is only one month old.
What is the moon
What single digit appears most frequently between and including the numbers 1 and 1,000? Hint: look for a pattern!
The most common digit is 1! Did you figure out why? Every number 1-9 appears exactly the same number of times in every ten numbers. But because we included the number 1,000, there’s an extra occurrence of the number 1. In total, the number 1 appears 301 times, and every other number appears 300 times.
You know 2 + 2 comes to the same as 2 x 2. Now find a set of three different whole numbers whose sum is equal to their total when multiplied.
The three different whole numbers whose sum is equal to their total when multiplied are 1, 2, and 3.
My twin lives at the reverse of my house number. The difference between our house numbers ends in two. What are the lowest possible numbers of our house numbers?
The lowest possible numbers for the houses are 19 and 91. The difference is 72.
What is the smallest whole number that is equal to seven times the sum of its digits?
21
A small number of cards has been lost from a complete pack. If I deal among four people, three cards remain. If I deal among three people, two remain and if I deal among five people, two cards remain. How many cards are there?
This one is pretty tricky, but the answer is: There are 47 cards. To get the answer, you need to know that there are 52 cards in a pack. Then, find the multiples of four, three, and five closest to that number, and see if any of them are the same. For example, you can deal 42, 44, and 48 cards amongst four people, which would mean 9, 5, or 1 cards is missing (with three remaining). However, the only one that works for multiples of three and five people is when five cards are missing, which gives us a total of 47 cards.
Old Granny Adams left half her money to her granddaughter and half that amount to her grandson. She left a sixth to her brother, and the remainder, $1,000, to the dogs’ home. How much did she leave altogether?
Adding one half, one quarter, and one sixth tells us that the total is a fraction of twelfths (2+4+6=12). You can also think about it as 6/12, 3/12, 2/12, which equals 11/12. If the remainder is $1,000, that must be one-twelfth, so the total is $12,000.
I add six to eleven, and get five. Why is this correct?
This numbers riddle is designed to trip you up! You have to think more broadly. When it is 11 a.m., adding six hours makes it 5 p.m.
One brother says of his younger brother: “Two years ago, I was three times as old as my brother was. In three years’ time, I will be twice as old as my brother.” How old are they each now?
The older brother will be twice as old as his younger brother in three years’ time. This immediately rules out the older brother currently being 8, 11, and 14, so he must be 17, and the younger brother 7. Two years ago, they were 15 and 5 respectively, and in three years’ time, they will be 20 and 10.
What starts with the letter P ends with the letter E and has a 1000 letters in it?
What is a post office?
In reply to an inquiry about the animals on his farm, the farmer says: “I only ever keep sheep, goats, and horses. In fact, at the moment they are all sheep but three, all goats but four, and all horses but five.” How many does he have of each animal?
The farmer has 3 sheep, 2 goats, and 1 horse.