What 5-digit number satisfies the following requirements?

1. No zeroes
2. First two digits are the same
3. Fourth digit is twice the first
4. Last digit is twice the third
5. Sum of all digits is 18

I am the owner of a pet store. If I put in one canary per cage, I have one bird too many. If I put in two canaries per cage, I have one cage too many. How many cages and canaries do I have?

At a quirky fruit stand, an orange costs 18 cents, a pineapple costs 27 cents and a grape costs 15 cents. Using the same logic, how much does a mango cost?

There is an abandoned aquarium in an empty house. The aquarium has three large fish and three small fish. But after a week, one large fish and two small fish die.

How many remain in the aquarium?

Here is the Roman numeral for nine: IX

By adding only one line or symbol, how can you turn it into six?

Which of the following words is the odd one out?

Chocolate
Biscuit
Lemonade
Jelly
Cake