Which is the smallest number that you can write using all the vowels exactly once?

Prove that the below maths equation is true.

8 + 8 = 91

If two's company, and three's a crowd, then whats four and five ?

Find the next number in the sequence

5 12 24 36 ?

What is full of holes but still holds water?

There are three light switches outside a room. One of the switches is connected to a light bulb inside the room.
Each of the three switches can be either 'ON' or 'OFF'.

You are allowed to set each switch the way you want it and then enter the room(note: you can enter the room only once)

Your task is to then determine which switch controls the bulb?

Can you make numbers like 24, using numbers 3,3,7 & 7 with any arithmetic operator?

What English word has three consecutive double letters?

Take one out and scratch my head, I am now black but once was red. What am I?

What does this rebus riddle means ?