642145 ÷ 80 
The aim is to understand the frequency of 80 in 642145.

Going ahead to step 1:
When dividing 6 by 80, we get 0 with a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Grab the next digit (4) from the dividend, add it to 6, then carry on: 64 / 80

Advancing to step 2:
The number 80 fits into 64 0 times, leaving a remainder of 64.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 64 after subtracting 0 from 64.
Bring next digit (2) of the dividend behind the 64 and repeat the process: 642 / 80

Advancing to step 3:
When dividing 642 by 80, we get 8 with a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 8.0
Subtract 640 from 642 to get 2.
Grab the next digit (1) from the dividend, add it to 2, then carry on: 21 / 80

On to step 4:
80 goes into 21 0 times with a remainder of 21.
Put 0 as the next digit of the answer. 
Result so far: 80.0
Subtracting 0 from 21 leaves us with 21.
Bring next digit (4) of the dividend behind the 21 and repeat the process: 214 / 80

Going ahead to step 5:
80 goes into 214 2 times with a remainder of 54.
Record the quotient 2 as the next digit in the result. 
Result so far: 802.0
Subtracting 160 from 214 leaves us with 54.
Fetch the next digit (5) from the dividend, attach it to 54 and continue: 545 / 80

Advancing to step 6:
80 can be fit into 545 6 times, resulting in a remainder of 65.
Put 6 as the next digit of the answer. 
Result so far: 8026.0
Deduct 480 from 545 and we're left with 65.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

Let's proceed to step 7:
80 can be fit into 650 8 times, resulting in a remainder of 10.
The next digit of our result is 8. 
Result so far: 8026.8
If we take 640 away from 650, we end up with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Moving on to step 8:
80 goes into 100 1 times with a remainder of 20.
Use 1 as the next digit of our solution. 
Result so far: 8026.81
Subtract 80 from 100 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Moving on to step 9:
80 can be fit into 200 2 times, resulting in a remainder of 40.
Record the quotient 2 as the next digit in the result. 
Result so far: 8026.812
Subtracting 160 from 200 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Going ahead to step 10:
400 divided by 80 is 5 with a remainder of 0.
Put 5 as the next digit of the answer. 
Result so far: 8026.8125
If we take 400 away from 400, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 11:
0 divided by 80 is 0 with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 8026.8125
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 12:
If we divide 0 by 80, we get 0 and a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 8026.8125
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Our division results in 8026.8125 with a remaining 0.0.