We look at the division of 73159455 by 438 
The aim is to understand the frequency of 438 in 73159455.

Advancing to step 1:
When dividing 7 by 438, we get 0 with a remainder of 7.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 7 and we're left with 7.
Fetch the next digit (3) from the dividend, attach it to 7 and continue: 73 / 438

Let's proceed to step 2:
438 goes into 73 0 times with a remainder of 73.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 73, we end up with 73.
Include the next digit (1) from the dividend after 73, then repeat: 731 / 438

Advancing to step 3:
438 can be fit into 731 1 times, resulting in a remainder of 293.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtracting 438 from 731 leaves us with 293.
Append the next digit (5) from the dividend to 293 and continue with: 2935 / 438

On to step 4:
2935 divided by 438 is 6 with a remainder of 307.
Use 6 as the next digit of our solution. 
Result so far: 16.0
Subtracting 2628 from 2935 leaves us with 307.
Fetch the next digit (9) from the dividend, attach it to 307 and continue: 3079 / 438

Let's proceed to step 5:
438 can be fit into 3079 7 times, resulting in a remainder of 13.
The number 7 becomes the next digit in our result. 
Result so far: 167.0
If we subtract 3066 from 3079, we get 13.
Bring next digit (4) of the dividend behind the 13 and repeat the process: 134 / 438

On to step 6:
The number 438 fits into 134 0 times, leaving a remainder of 134.
The number 0 becomes the next digit in our result. 
Result so far: 1670.0
The remainder is 134 after subtracting 0 from 134.
Include the next digit (5) from the dividend after 134, then repeat: 1345 / 438

Going ahead to step 7:
438 can be fit into 1345 3 times, resulting in a remainder of 31.
Put 3 as the next digit of the answer. 
Result so far: 16703.0
Deduct 1314 from 1345 and we're left with 31.
Take the next digit (5) from the dividend and append it to 31, then repeat: 315 / 438

Let's proceed to step 8:
When dividing 315 by 438, we get 0 with a remainder of 315.
The next digit of our result is 0. 
Result so far: 167030.0
If we take 0 away from 315, we end up with 315.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3150, and continue the process.

On to step 9:
If we divide 3150 by 438, we get 7 and a remainder of 84.
Write down 7 as next digit of the result. 
Result so far: 167030.7
Subtracting 3066 from 3150 leaves us with 84.
Since there are no more digits in the dividend, we add a zero to the remainder making it 840, and continue the process.

Moving on to step 10:
438 goes into 840 1 times with a remainder of 402.
Put 1 as the next digit of the answer. 
Result so far: 167030.71
Subtract 438 from 840 to get 402.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4020, and continue the process.

Moving on to step 11:
The number 438 fits into 4020 9 times, leaving a remainder of 78.
The number 9 becomes the next digit in our result. 
Result so far: 167030.719
Subtract 3942 from 4020 to get 78.
Since there are no more digits in the dividend, we add a zero to the remainder making it 780, and continue the process.

Advancing to step 12:
The number 438 fits into 780 1 times, leaving a remainder of 342.
Use 1 as the next digit of our solution. 
Result so far: 167030.7191
If we subtract 438 from 780, we get 342.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3420, and continue the process.

On to step 13:
If we divide 3420 by 438, we get 7 and a remainder of 354.
Record the quotient 7 as the next digit in the result. 
Result so far: 167030.71917
Subtract 3066 from 3420 to get 354.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3540, and continue the process.

Moving on to step 14:
If we divide 3540 by 438, we get 8 and a remainder of 36.
Record the quotient 8 as the next digit in the result. 
Result so far: 167030.719178
If we subtract 3504 from 3540, we get 36.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

On to step 15:
The number 438 fits into 360 0 times, leaving a remainder of 360.
Record the quotient 0 as the next digit in the result. 
Result so far: 167030.719178
If we take 0 away from 360, we end up with 360.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3600, and continue the process.

Step 16:
3600 divided by 438 is 8 with a remainder of 96.
The next digit of our result is 8. 
Result so far: 167030.71917808
Subtracting 3504 from 3600 leaves us with 96.
Since there are no more digits in the dividend, we add a zero to the remainder making it 960, and continue the process.

The final outcome is 167030.71917808, with a leftover of 9.6e-08.