We look at the division of 69858977 by 520 
The aim is to understand the frequency of 520 in 69858977.

On to step 1:
When dividing 6 by 520, we get 0 with a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Fetch the next digit (9) from the dividend, attach it to 6 and continue: 69 / 520

Step 2:
The number 520 fits into 69 0 times, leaving a remainder of 69.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 69 to get 69.
Append the next digit (8) from the dividend to 69 and continue with: 698 / 520

Advancing to step 3:
698 divided by 520 is 1 with a remainder of 178.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtract 520 from 698 to get 178.
Fetch the next digit (5) from the dividend, attach it to 178 and continue: 1785 / 520

Step 4:
1785 divided by 520 is 3 with a remainder of 225.
The number 3 becomes the next digit in our result. 
Result so far: 13.0
Deduct 1560 from 1785 and we're left with 225.
Bring next digit (8) of the dividend behind the 225 and repeat the process: 2258 / 520

Going ahead to step 5:
2258 divided by 520 is 4 with a remainder of 178.
Write down 4 as next digit of the result. 
Result so far: 134.0
Subtracting 2080 from 2258 leaves us with 178.
Include the next digit (9) from the dividend after 178, then repeat: 1789 / 520

Let's proceed to step 6:
520 goes into 1789 3 times with a remainder of 229.
The next digit of our result is 3. 
Result so far: 1343.0
Subtract 1560 from 1789 to get 229.
Append the next digit (7) from the dividend to 229 and continue with: 2297 / 520

Step 7:
2297 divided by 520 is 4 with a remainder of 217.
Record the quotient 4 as the next digit in the result. 
Result so far: 13434.0
Subtracting 2080 from 2297 leaves us with 217.
Bring next digit (7) of the dividend behind the 217 and repeat the process: 2177 / 520

Moving on to step 8:
When dividing 2177 by 520, we get 4 with a remainder of 97.
Use 4 as the next digit of our solution. 
Result so far: 134344.0
If we take 2080 away from 2177, we end up with 97.
Since there are no more digits in the dividend, we add a zero to the remainder making it 970, and continue the process.

Let's proceed to step 9:
If we divide 970 by 520, we get 1 and a remainder of 450.
Use 1 as the next digit of our solution. 
Result so far: 134344.1
Subtracting 520 from 970 leaves us with 450.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4500, and continue the process.

Advancing to step 10:
520 goes into 4500 8 times with a remainder of 340.
Record the quotient 8 as the next digit in the result. 
Result so far: 134344.18
Deduct 4160 from 4500 and we're left with 340.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3400, and continue the process.

Advancing to step 11:
520 goes into 3400 6 times with a remainder of 280.
Write down 6 as next digit of the result. 
Result so far: 134344.186
Deduct 3120 from 3400 and we're left with 280.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2800, and continue the process.

Let's proceed to step 12:
The number 520 fits into 2800 5 times, leaving a remainder of 200.
The number 5 becomes the next digit in our result. 
Result so far: 134344.1865
If we subtract 2600 from 2800, we get 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2000, and continue the process.

Let's proceed to step 13:
520 can be fit into 2000 3 times, resulting in a remainder of 440.
Write down 3 as next digit of the result. 
Result so far: 134344.18653
If we take 1560 away from 2000, we end up with 440.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4400, and continue the process.

On to step 14:
520 can be fit into 4400 8 times, resulting in a remainder of 240.
Put 8 as the next digit of the answer. 
Result so far: 134344.186538
The remainder is 240 after subtracting 4160 from 4400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2400, and continue the process.

Let's proceed to step 15:
When dividing 2400 by 520, we get 4 with a remainder of 320.
Record the quotient 4 as the next digit in the result. 
Result so far: 134344.1865384
The remainder is 320 after subtracting 2080 from 2400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3200, and continue the process.

Going ahead to step 16:
520 can be fit into 3200 6 times, resulting in a remainder of 80.
Put 6 as the next digit of the answer. 
Result so far: 134344.18653846
The remainder is 80 after subtracting 3120 from 3200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Our division results in 134344.18653846 with a remaining 8e-08.