Count the number of lines in the image below ?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

What's a single-digit number with no value?

On her drawing table, Sayna lit 12 coloured candles. A few seconds later she blew two candles off.

How many candles Sayna have at the end?

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?

An exterior architect is asked by a builder to plant seven trees in a manner that there are exactly six rows of trees in a straight line and each row has three trees in particular.

How will he do it?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

If 1+9+8=1, what is 2+8+9?

Below, you will find the mathematical proof that 10 equals 9.99999?. But is that possible or there is something wrong about it? Can you find the error?

x = 9.999999...
10x = 99.999999...
10x - x = 90
9x = 90
x = 10

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