350578 ÷ 80 
The aim is to understand the frequency of 80 in 350578.

Step 1:
When dividing 3 by 80, we get 0 with a remainder of 3.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 3, we end up with 3.
Take the next digit (5) from the dividend and append it to 3, then repeat: 35 / 80

Going ahead to step 2:
The number 80 fits into 35 0 times, leaving a remainder of 35.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 35 and we're left with 35.
Grab the next digit (0) from the dividend, add it to 35, then carry on: 350 / 80

On to step 3:
80 can be fit into 350 4 times, resulting in a remainder of 30.
Record the quotient 4 as the next digit in the result. 
Result so far: 4.0
Deduct 320 from 350 and we're left with 30.
Take the next digit (5) from the dividend and append it to 30, then repeat: 305 / 80

Advancing to step 4:
305 divided by 80 is 3 with a remainder of 65.
Use 3 as the next digit of our solution. 
Result so far: 43.0
Subtract 240 from 305 to get 65.
Append the next digit (7) from the dividend to 65 and continue with: 657 / 80

Advancing to step 5:
657 divided by 80 is 8 with a remainder of 17.
Record the quotient 8 as the next digit in the result. 
Result so far: 438.0
Subtract 640 from 657 to get 17.
Include the next digit (8) from the dividend after 17, then repeat: 178 / 80

Step 6:
When dividing 178 by 80, we get 2 with a remainder of 18.
Put 2 as the next digit of the answer. 
Result so far: 4382.0
Deduct 160 from 178 and we're left with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Moving on to step 7:
The number 80 fits into 180 2 times, leaving a remainder of 20.
Put 2 as the next digit of the answer. 
Result so far: 4382.2
The remainder is 20 after subtracting 160 from 180.
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 8:
When dividing 200 by 80, we get 2 with a remainder of 40.
Use 2 as the next digit of our solution. 
Result so far: 4382.22
Subtract 160 from 200 to get 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

The quotient of the division is 4382.22, and the remainder is 0.04.