How to find all the prime numbers from 1-100 to find HCF and LCM for mathematical application

 We all have a phone number to call a person.Likewise these prime numbers also have phone number to call them.Let's see that now.

NOTE:Numbers written in Green are prime numbers.

If you look at the above picture you can see that there are numbers at the side for each 10 set of numbers.The phone number column is the number to call the prime numbers.

If you see the first set i.e 1 to 10 ,the no 4 is in the ph.no column.That means,that there are 4 prime nos in the first set.

If you see the third set i.e 21 to 30,the no 2 is in the ph.no column.That means that there are 2 prime nos in the third set.

In this method we can know the number of prime nos in each set.

To remember the phone number:

We always do not forget the first no i.e 4.Repeat it for another time i.e 44

Half of 44 is 22.So,its known that the next two nos are 22 i.e 4422

The consecutive number of 2 is 3.So the next no is 3 i.e 44223

Again put 22 after 3 i.e 44223 22

The consecutive number of 2 is 3.So the next no is 3 i.e 44223 223

The predecessor of 3 is 2 .So, the next no is 2 i.e 44223 2232

The predecessor of 2 is 1 .So the next no is 1 i.e 44223 22321

Now we got our phone number for our prime nos.

If its very difficult to follow the formula just simply byheart the phone number

-the simplest way of all😊