521289 divided by 80 
The aim is to understand the frequency of 80 in 521289.

Moving on to step 1:
80 goes into 5 0 times with a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 5, we get 5.
Take the next digit (2) from the dividend and append it to 5, then repeat: 52 / 80

Advancing to step 2:
The number 80 fits into 52 0 times, leaving a remainder of 52.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 52 after subtracting 0 from 52.
Take the next digit (1) from the dividend and append it to 52, then repeat: 521 / 80

Let's proceed to step 3:
When dividing 521 by 80, we get 6 with a remainder of 41.
The number 6 becomes the next digit in our result. 
Result so far: 6.0
Subtracting 480 from 521 leaves us with 41.
Fetch the next digit (2) from the dividend, attach it to 41 and continue: 412 / 80

Step 4:
When dividing 412 by 80, we get 5 with a remainder of 12.
Use 5 as the next digit of our solution. 
Result so far: 65.0
Subtract 400 from 412 to get 12.
Bring next digit (8) of the dividend behind the 12 and repeat the process: 128 / 80

Moving on to step 5:
128 divided by 80 is 1 with a remainder of 48.
The number 1 becomes the next digit in our result. 
Result so far: 651.0
If we take 80 away from 128, we end up with 48.
Bring next digit (9) of the dividend behind the 48 and repeat the process: 489 / 80

Moving on to step 6:
If we divide 489 by 80, we get 6 and a remainder of 9.
Put 6 as the next digit of the answer. 
Result so far: 6516.0
Deduct 480 from 489 and we're left with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Going ahead to step 7:
The number 80 fits into 90 1 times, leaving a remainder of 10.
Use 1 as the next digit of our solution. 
Result so far: 6516.1
If we subtract 80 from 90, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Let's proceed to step 8:
80 can be fit into 100 1 times, resulting in a remainder of 20.
Record the quotient 1 as the next digit in the result. 
Result so far: 6516.11
Deduct 80 from 100 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Our division results in 6516.11 with a remaining 0.02.