If 21x = 79x, what is the value of x?

If you say my name, I will no longer exist. What am I?

A car meter reading shows 72927 miles a palindromic number.
what is the minimum number of miles you would need to travel to see another palindromic number on the car meter reading?

We have arranged an array of numbers below. What you have to do is use any kind of mathematical symbol you know excluding any symbol that contains a number like cube root. You can use any amount of symbols but you have to come up with a valid equation for all of them.

0 0 0 = 6
1 1 1 = 6
2 + 2 + 2 = 6
3 3 3 = 6
4 4 4 = 6
5 5 5 = 6
6 6 6 = 6
7 7 7 = 6
8 8 8 = 6
9 9 9 = 6

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

Spelt forwards I’m what you do every day, spelled backwards I’m something you hate. What am I?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

I have an eye but still cannot see.

Who am I?

Can you find the odd number in the following five choices?

1) 482636
2) 259807
3) 865195
4) 104739
5) 391744