We look at the division of 66879459 by 610 
The aim is to understand the frequency of 610 in 66879459.

Advancing to step 1:
If we divide 6 by 610, we get 0 and a remainder of 6.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 6, we end up with 6.
Take the next digit (6) from the dividend and append it to 6, then repeat: 66 / 610

Going ahead to step 2:
610 goes into 66 0 times with a remainder of 66.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 66 to get 66.
Grab the next digit (8) from the dividend, add it to 66, then carry on: 668 / 610

On to step 3:
668 divided by 610 is 1 with a remainder of 58.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we take 610 away from 668, we end up with 58.
Fetch the next digit (7) from the dividend, attach it to 58 and continue: 587 / 610

Moving on to step 4:
587 divided by 610 is 0 with a remainder of 587.
Use 0 as the next digit of our solution. 
Result so far: 10.0
The remainder is 587 after subtracting 0 from 587.
Append the next digit (9) from the dividend to 587 and continue with: 5879 / 610

Advancing to step 5:
610 can be fit into 5879 9 times, resulting in a remainder of 389.
The number 9 becomes the next digit in our result. 
Result so far: 109.0
Deduct 5490 from 5879 and we're left with 389.
Include the next digit (4) from the dividend after 389, then repeat: 3894 / 610

Let's proceed to step 6:
When dividing 3894 by 610, we get 6 with a remainder of 234.
Use 6 as the next digit of our solution. 
Result so far: 1096.0
If we take 3660 away from 3894, we end up with 234.
Bring next digit (5) of the dividend behind the 234 and repeat the process: 2345 / 610

Step 7:
610 can be fit into 2345 3 times, resulting in a remainder of 515.
Write down 3 as next digit of the result. 
Result so far: 10963.0
If we take 1830 away from 2345, we end up with 515.
Include the next digit (9) from the dividend after 515, then repeat: 5159 / 610

Let's proceed to step 8:
The number 610 fits into 5159 8 times, leaving a remainder of 279.
Put 8 as the next digit of the answer. 
Result so far: 109638.0
If we subtract 4880 from 5159, we get 279.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2790, and continue the process.

Advancing to step 9:
610 goes into 2790 4 times with a remainder of 350.
Write down 4 as next digit of the result. 
Result so far: 109638.4
If we take 2440 away from 2790, we end up with 350.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3500, and continue the process.

Let's proceed to step 10:
The number 610 fits into 3500 5 times, leaving a remainder of 450.
The next digit of our result is 5. 
Result so far: 109638.45
Subtract 3050 from 3500 to get 450.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4500, and continue the process.

Going ahead to step 11:
4500 divided by 610 is 7 with a remainder of 230.
Use 7 as the next digit of our solution. 
Result so far: 109638.457
The remainder is 230 after subtracting 4270 from 4500.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2300, and continue the process.

On to step 12:
When dividing 2300 by 610, we get 3 with a remainder of 470.
Put 3 as the next digit of the answer. 
Result so far: 109638.4573
If we subtract 1830 from 2300, we get 470.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4700, and continue the process.

Moving on to step 13:
If we divide 4700 by 610, we get 7 and a remainder of 430.
Put 7 as the next digit of the answer. 
Result so far: 109638.45737
If we take 4270 away from 4700, we end up with 430.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4300, and continue the process.

Moving on to step 14:
610 goes into 4300 7 times with a remainder of 30.
The next digit of our result is 7. 
Result so far: 109638.457377
Subtracting 4270 from 4300 leaves us with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

The final outcome is 109638.457377, with a leftover of 3e-06.