9991642 divided by 161 
The aim is to understand the frequency of 161 in 9991642.

Step 1:
161 goes into 9 0 times with a remainder of 9.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 9 and we're left with 9.
Include the next digit (9) from the dividend after 9, then repeat: 99 / 161

On to step 2:
161 can be fit into 99 0 times, resulting in a remainder of 99.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 99 to get 99.
Bring next digit (9) of the dividend behind the 99 and repeat the process: 999 / 161

On to step 3:
161 can be fit into 999 6 times, resulting in a remainder of 33.
The next digit of our result is 6. 
Result so far: 6.0
If we take 966 away from 999, we end up with 33.
Bring next digit (1) of the dividend behind the 33 and repeat the process: 331 / 161

On to step 4:
161 can be fit into 331 2 times, resulting in a remainder of 9.
Record the quotient 2 as the next digit in the result. 
Result so far: 62.0
Deduct 322 from 331 and we're left with 9.
Fetch the next digit (6) from the dividend, attach it to 9 and continue: 96 / 161

Step 5:
When dividing 96 by 161, we get 0 with a remainder of 96.
Record the quotient 0 as the next digit in the result. 
Result so far: 620.0
The remainder is 96 after subtracting 0 from 96.
Append the next digit (4) from the dividend to 96 and continue with: 964 / 161

Let's proceed to step 6:
964 divided by 161 is 5 with a remainder of 159.
Record the quotient 5 as the next digit in the result. 
Result so far: 6205.0
The remainder is 159 after subtracting 805 from 964.
Append the next digit (2) from the dividend to 159 and continue with: 1592 / 161

Advancing to step 7:
161 can be fit into 1592 9 times, resulting in a remainder of 143.
Use 9 as the next digit of our solution. 
Result so far: 62059.0
If we take 1449 away from 1592, we end up with 143.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1430, and continue the process.

Moving on to step 8:
When dividing 1430 by 161, we get 8 with a remainder of 142.
Write down 8 as next digit of the result. 
Result so far: 62059.8
Deduct 1288 from 1430 and we're left with 142.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1420, and continue the process.

Advancing to step 9:
If we divide 1420 by 161, we get 8 and a remainder of 132.
Write down 8 as next digit of the result. 
Result so far: 62059.88
If we take 1288 away from 1420, we end up with 132.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1320, and continue the process.

After the division, we end up with 62059.88 and a remainder of 0.132.