We look at the division of 26121403 by 869 
The aim is to understand the frequency of 869 in 26121403.

Going ahead to step 1:
The number 869 fits into 2 0 times, leaving a remainder of 2.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 2 leaves us with 2.
Include the next digit (6) from the dividend after 2, then repeat: 26 / 869

On to step 2:
If we divide 26 by 869, we get 0 and a remainder of 26.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 26 and we're left with 26.
Take the next digit (1) from the dividend and append it to 26, then repeat: 261 / 869

Advancing to step 3:
869 goes into 261 0 times with a remainder of 261.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 261 after subtracting 0 from 261.
Append the next digit (2) from the dividend to 261 and continue with: 2612 / 869

Advancing to step 4:
2612 divided by 869 is 3 with a remainder of 5.
Put 3 as the next digit of the answer. 
Result so far: 3.0
If we take 2607 away from 2612, we end up with 5.
Append the next digit (1) from the dividend to 5 and continue with: 51 / 869

Advancing to step 5:
51 divided by 869 is 0 with a remainder of 51.
Use 0 as the next digit of our solution. 
Result so far: 30.0
Subtract 0 from 51 to get 51.
Fetch the next digit (4) from the dividend, attach it to 51 and continue: 514 / 869

Going ahead to step 6:
514 divided by 869 is 0 with a remainder of 514.
Put 0 as the next digit of the answer. 
Result so far: 300.0
Subtract 0 from 514 to get 514.
Append the next digit (0) from the dividend to 514 and continue with: 5140 / 869

Step 7:
5140 divided by 869 is 5 with a remainder of 795.
The next digit of our result is 5. 
Result so far: 3005.0
Deduct 4345 from 5140 and we're left with 795.
Append the next digit (3) from the dividend to 795 and continue with: 7953 / 869

Step 8:
If we divide 7953 by 869, we get 9 and a remainder of 132.
Use 9 as the next digit of our solution. 
Result so far: 30059.0
Subtract 7821 from 7953 to get 132.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1320, and continue the process.

Step 9:
869 can be fit into 1320 1 times, resulting in a remainder of 451.
Put 1 as the next digit of the answer. 
Result so far: 30059.1
Subtract 869 from 1320 to get 451.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4510, and continue the process.

On to step 10:
When dividing 4510 by 869, we get 5 with a remainder of 165.
Write down 5 as next digit of the result. 
Result so far: 30059.15
The remainder is 165 after subtracting 4345 from 4510.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1650, and continue the process.

Moving on to step 11:
The number 869 fits into 1650 1 times, leaving a remainder of 781.
Put 1 as the next digit of the answer. 
Result so far: 30059.151
Subtract 869 from 1650 to get 781.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7810, and continue the process.

Step 12:
The number 869 fits into 7810 8 times, leaving a remainder of 858.
The number 8 becomes the next digit in our result. 
Result so far: 30059.1518
If we take 6952 away from 7810, we end up with 858.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8580, and continue the process.

Step 13:
8580 divided by 869 is 9 with a remainder of 759.
The next digit of our result is 9. 
Result so far: 30059.15189
Deduct 7821 from 8580 and we're left with 759.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7590, and continue the process.

Step 14:
The number 869 fits into 7590 8 times, leaving a remainder of 638.
Write down 8 as next digit of the result. 
Result so far: 30059.151898
Subtracting 6952 from 7590 leaves us with 638.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6380, and continue the process.

Advancing to step 15:
If we divide 6380 by 869, we get 7 and a remainder of 297.
The next digit of our result is 7. 
Result so far: 30059.1518987
Deduct 6083 from 6380 and we're left with 297.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2970, and continue the process.

Let's proceed to step 16:
2970 divided by 869 is 3 with a remainder of 363.
Put 3 as the next digit of the answer. 
Result so far: 30059.15189873
If we take 2607 away from 2970, we end up with 363.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3630, and continue the process.

The final outcome is 30059.15189873, with a leftover of 3.63e-07.