What does it mean?

One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

2, 3, 5, 9, 17, _ What is the next number in the sequence?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

What has many teeth, but cannot bite?

Count the number of balls in picture below:

Replace the question mark with the number below given a simple math problem.

What work can one never finish?

Can you write down eight eights so that they add up to one thousand?

There are three boxes of different sizes with three cupcakes inside each of the boxes in Christina's kitchen. At night her daughter wakes up and goes to the kitchen. She opens a box and eats all three cakes.

But in the morning Christina finds out that each box still had three cupcakes. How?