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

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

The following four words might seem abrupt to you. But you can make them meaningful by just adding vowels.
RDSH
GGPLNT
TMT
NN

Hint: All of them are vegetables.

Rumel, A detective who was mere days from cracking an international smuggling ring has suddenly gone missing. While inspecting his last-known location, you find a note:

710 57735 34 5508 51 7718

Currently, there are 3 suspects: Bill, John, and Todd. Can you break the detective's code and find the criminal's name?

Get total of 120 by using five zeros 0,0,0,0,0 and any one mathematical operator.
Do you ?

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

If you read clockwise, you can form a word by inserting three missing letters in the picture given below. Can you do it?

Solve the following series:
AZ, GT, MN, __, YB

I had an infinite supply of water and 5 litres and 3 litres jars.

How would you measure exactly 4 litres in the least number of steps?

A maths symbol is hidden in the below Bar Graph. Can you decipher it?