62974603 ÷ 646 
The aim is to understand the frequency of 646 in 62974603.

On to step 1:
646 can be fit into 6 0 times, resulting in a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Bring next digit (2) of the dividend behind the 6 and repeat the process: 62 / 646

On to step 2:
If we divide 62 by 646, we get 0 and a remainder of 62.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 62 leaves us with 62.
Bring next digit (9) of the dividend behind the 62 and repeat the process: 629 / 646

On to step 3:
The number 646 fits into 629 0 times, leaving a remainder of 629.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 629 after subtracting 0 from 629.
Append the next digit (7) from the dividend to 629 and continue with: 6297 / 646

Let's proceed to step 4:
6297 divided by 646 is 9 with a remainder of 483.
The next digit of our result is 9. 
Result so far: 9.0
If we subtract 5814 from 6297, we get 483.
Bring next digit (4) of the dividend behind the 483 and repeat the process: 4834 / 646

Going ahead to step 5:
The number 646 fits into 4834 7 times, leaving a remainder of 312.
Use 7 as the next digit of our solution. 
Result so far: 97.0
If we subtract 4522 from 4834, we get 312.
Fetch the next digit (6) from the dividend, attach it to 312 and continue: 3126 / 646

Moving on to step 6:
The number 646 fits into 3126 4 times, leaving a remainder of 542.
Write down 4 as next digit of the result. 
Result so far: 974.0
The remainder is 542 after subtracting 2584 from 3126.
Grab the next digit (0) from the dividend, add it to 542, then carry on: 5420 / 646

Going ahead to step 7:
5420 divided by 646 is 8 with a remainder of 252.
Write down 8 as next digit of the result. 
Result so far: 9748.0
If we subtract 5168 from 5420, we get 252.
Include the next digit (3) from the dividend after 252, then repeat: 2523 / 646

Step 8:
646 goes into 2523 3 times with a remainder of 585.
Write down 3 as next digit of the result. 
Result so far: 97483.0
Deduct 1938 from 2523 and we're left with 585.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5850, and continue the process.

Step 9:
646 can be fit into 5850 9 times, resulting in a remainder of 36.
The next digit of our result is 9. 
Result so far: 97483.9
The remainder is 36 after subtracting 5814 from 5850.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

Moving on to step 10:
The number 646 fits into 360 0 times, leaving a remainder of 360.
The next digit of our result is 0. 
Result so far: 97483.9
If we take 0 away from 360, we end up with 360.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3600, and continue the process.

Step 11:
646 goes into 3600 5 times with a remainder of 370.
Record the quotient 5 as the next digit in the result. 
Result so far: 97483.905
If we take 3230 away from 3600, we end up with 370.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3700, and continue the process.

Going ahead to step 12:
If we divide 3700 by 646, we get 5 and a remainder of 470.
Record the quotient 5 as the next digit in the result. 
Result so far: 97483.9055
Deduct 3230 from 3700 and we're left with 470.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4700, and continue the process.

The final outcome is 97483.9055, with a leftover of 0.0047.