7278554 ÷ 661 
The aim is to understand the frequency of 661 in 7278554.

Going ahead to step 1:
661 goes into 7 0 times with a remainder of 7.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Bring next digit (2) of the dividend behind the 7 and repeat the process: 72 / 661

Moving on to step 2:
72 divided by 661 is 0 with a remainder of 72.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 72, we get 72.
Take the next digit (7) from the dividend and append it to 72, then repeat: 727 / 661

On to step 3:
When dividing 727 by 661, we get 1 with a remainder of 66.
Write down 1 as next digit of the result. 
Result so far: 1.0
Subtract 661 from 727 to get 66.
Append the next digit (8) from the dividend to 66 and continue with: 668 / 661

On to step 4:
When dividing 668 by 661, we get 1 with a remainder of 7.
Put 1 as the next digit of the answer. 
Result so far: 11.0
Subtracting 661 from 668 leaves us with 7.
Append the next digit (5) from the dividend to 7 and continue with: 75 / 661

On to step 5:
661 goes into 75 0 times with a remainder of 75.
Record the quotient 0 as the next digit in the result. 
Result so far: 110.0
If we take 0 away from 75, we end up with 75.
Take the next digit (5) from the dividend and append it to 75, then repeat: 755 / 661

Let's proceed to step 6:
If we divide 755 by 661, we get 1 and a remainder of 94.
Record the quotient 1 as the next digit in the result. 
Result so far: 1101.0
The remainder is 94 after subtracting 661 from 755.
Take the next digit (4) from the dividend and append it to 94, then repeat: 944 / 661

Step 7:
If we divide 944 by 661, we get 1 and a remainder of 283.
The number 1 becomes the next digit in our result. 
Result so far: 11011.0
Subtract 661 from 944 to get 283.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2830, and continue the process.

Step 8:
2830 divided by 661 is 4 with a remainder of 186.
Use 4 as the next digit of our solution. 
Result so far: 11011.4
The remainder is 186 after subtracting 2644 from 2830.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1860, and continue the process.

Step 9:
When dividing 1860 by 661, we get 2 with a remainder of 538.
The next digit of our result is 2. 
Result so far: 11011.42
If we take 1322 away from 1860, we end up with 538.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5380, and continue the process.

Step 10:
When dividing 5380 by 661, we get 8 with a remainder of 92.
The number 8 becomes the next digit in our result. 
Result so far: 11011.428
If we take 5288 away from 5380, we end up with 92.
Since there are no more digits in the dividend, we add a zero to the remainder making it 920, and continue the process.

Step 11:
When dividing 920 by 661, we get 1 with a remainder of 259.
Use 1 as the next digit of our solution. 
Result so far: 11011.4281
Subtracting 661 from 920 leaves us with 259.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2590, and continue the process.

Going ahead to step 12:
When dividing 2590 by 661, we get 3 with a remainder of 607.
The number 3 becomes the next digit in our result. 
Result so far: 11011.42813
Subtract 1983 from 2590 to get 607.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6070, and continue the process.

Advancing to step 13:
When dividing 6070 by 661, we get 9 with a remainder of 121.
The next digit of our result is 9. 
Result so far: 11011.428139
Subtract 5949 from 6070 to get 121.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1210, and continue the process.

Moving on to step 14:
661 can be fit into 1210 1 times, resulting in a remainder of 549.
The number 1 becomes the next digit in our result. 
Result so far: 11011.4281391
Deduct 661 from 1210 and we're left with 549.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5490, and continue the process.

On to step 15:
The number 661 fits into 5490 8 times, leaving a remainder of 202.
Write down 8 as next digit of the result. 
Result so far: 11011.42813918
Subtract 5288 from 5490 to get 202.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2020, and continue the process.

Our division results in 11011.42813918 with a remaining 2.02e-07.