We look at the division of 487478 by 77 
The aim is to understand the frequency of 77 in 487478.

Advancing to step 1:
The number 77 fits into 4 0 times, leaving a remainder of 4.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Include the next digit (8) from the dividend after 4, then repeat: 48 / 77

Going ahead to step 2:
The number 77 fits into 48 0 times, leaving a remainder of 48.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 48 leaves us with 48.
Append the next digit (7) from the dividend to 48 and continue with: 487 / 77

Going ahead to step 3:
77 goes into 487 6 times with a remainder of 25.
The next digit of our result is 6. 
Result so far: 6.0
If we take 462 away from 487, we end up with 25.
Grab the next digit (4) from the dividend, add it to 25, then carry on: 254 / 77

On to step 4:
When dividing 254 by 77, we get 3 with a remainder of 23.
Record the quotient 3 as the next digit in the result. 
Result so far: 63.0
If we take 231 away from 254, we end up with 23.
Include the next digit (7) from the dividend after 23, then repeat: 237 / 77

Going ahead to step 5:
77 goes into 237 3 times with a remainder of 6.
Write down 3 as next digit of the result. 
Result so far: 633.0
If we subtract 231 from 237, we get 6.
Grab the next digit (8) from the dividend, add it to 6, then carry on: 68 / 77

Moving on to step 6:
77 goes into 68 0 times with a remainder of 68.
Use 0 as the next digit of our solution. 
Result so far: 6330.0
Subtract 0 from 68 to get 68.
Since there are no more digits in the dividend, we add a zero to the remainder making it 680, and continue the process.

Advancing to step 7:
The number 77 fits into 680 8 times, leaving a remainder of 64.
The next digit of our result is 8. 
Result so far: 6330.8
If we subtract 616 from 680, we get 64.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

Going ahead to step 8:
When dividing 640 by 77, we get 8 with a remainder of 24.
The next digit of our result is 8. 
Result so far: 6330.88
If we take 616 away from 640, we end up with 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

After the division, we end up with 6330.88 and a remainder of 0.024.