We look at the division of 63840478 by 458 
The aim is to understand the frequency of 458 in 63840478.

Advancing to step 1:
458 goes into 6 0 times with a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Append the next digit (3) from the dividend to 6 and continue with: 63 / 458

Advancing to step 2:
When dividing 63 by 458, we get 0 with a remainder of 63.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 63, we get 63.
Grab the next digit (8) from the dividend, add it to 63, then carry on: 638 / 458

Moving on to step 3:
The number 458 fits into 638 1 times, leaving a remainder of 180.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Subtracting 458 from 638 leaves us with 180.
Take the next digit (4) from the dividend and append it to 180, then repeat: 1804 / 458

Let's proceed to step 4:
The number 458 fits into 1804 3 times, leaving a remainder of 430.
The number 3 becomes the next digit in our result. 
Result so far: 13.0
If we take 1374 away from 1804, we end up with 430.
Fetch the next digit (0) from the dividend, attach it to 430 and continue: 4300 / 458

Going ahead to step 5:
458 goes into 4300 9 times with a remainder of 178.
Record the quotient 9 as the next digit in the result. 
Result so far: 139.0
Subtracting 4122 from 4300 leaves us with 178.
Fetch the next digit (4) from the dividend, attach it to 178 and continue: 1784 / 458

Going ahead to step 6:
When dividing 1784 by 458, we get 3 with a remainder of 410.
Record the quotient 3 as the next digit in the result. 
Result so far: 1393.0
Deduct 1374 from 1784 and we're left with 410.
Grab the next digit (7) from the dividend, add it to 410, then carry on: 4107 / 458

On to step 7:
458 can be fit into 4107 8 times, resulting in a remainder of 443.
The number 8 becomes the next digit in our result. 
Result so far: 13938.0
The remainder is 443 after subtracting 3664 from 4107.
Take the next digit (8) from the dividend and append it to 443, then repeat: 4438 / 458

Step 8:
458 goes into 4438 9 times with a remainder of 316.
Put 9 as the next digit of the answer. 
Result so far: 139389.0
Deduct 4122 from 4438 and we're left with 316.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3160, and continue the process.

On to step 9:
The number 458 fits into 3160 6 times, leaving a remainder of 412.
Record the quotient 6 as the next digit in the result. 
Result so far: 139389.6
If we take 2748 away from 3160, we end up with 412.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4120, and continue the process.

On to step 10:
If we divide 4120 by 458, we get 8 and a remainder of 456.
The number 8 becomes the next digit in our result. 
Result so far: 139389.68
Subtract 3664 from 4120 to get 456.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4560, and continue the process.

Advancing to step 11:
4560 divided by 458 is 9 with a remainder of 438.
Record the quotient 9 as the next digit in the result. 
Result so far: 139389.689
Deduct 4122 from 4560 and we're left with 438.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4380, and continue the process.

Step 12:
4380 divided by 458 is 9 with a remainder of 258.
The number 9 becomes the next digit in our result. 
Result so far: 139389.6899
Subtracting 4122 from 4380 leaves us with 258.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2580, and continue the process.

The final result is 139389.6899 with a remainder of 0.00258.