Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

Replace the (?) with the correct mathematical signs to make the expression equal to 59.

18 ? 12 ? 4 ? 5 = 59

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

Replace the question mark with the correct number in below Picture:

A mules travels the same distance daily.
I noticed that two of his legs travels 10km and the remaining two travels 12km.
Obviously two mules legs cannot be a 2km ahead of the other 2.

The mules is perfectly normal. So how come this be true ?

The square root of number 121 is "11". What is the square root of the number "12345678987654321."?

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

Solve the mathematical equation in the picture below.

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

A man had five children. He had $100 with him to give to his children. He decided to start with the youngest child and then give $2 more than each younger child to his next elder child.

For example, if he gives $x to the youngest child, he will give $(x+2) to the next one, $[(x+2) + 2] to the next one and so on.

Can you find out how much did the youngest one receive?