We look at the division of 817090 by 493 
The aim is to understand the frequency of 493 in 817090.

On to step 1:
8 divided by 493 is 0 with a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 8 to get 8.
Append the next digit (1) from the dividend to 8 and continue with: 81 / 493

Moving on to step 2:
When dividing 81 by 493, we get 0 with a remainder of 81.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 81 to get 81.
Grab the next digit (7) from the dividend, add it to 81, then carry on: 817 / 493

Step 3:
The number 493 fits into 817 1 times, leaving a remainder of 324.
Put 1 as the next digit of the answer. 
Result so far: 1.0
If we take 493 away from 817, we end up with 324.
Take the next digit (0) from the dividend and append it to 324, then repeat: 3240 / 493

Step 4:
493 goes into 3240 6 times with a remainder of 282.
Record the quotient 6 as the next digit in the result. 
Result so far: 16.0
If we subtract 2958 from 3240, we get 282.
Grab the next digit (9) from the dividend, add it to 282, then carry on: 2829 / 493

Advancing to step 5:
When dividing 2829 by 493, we get 5 with a remainder of 364.
Record the quotient 5 as the next digit in the result. 
Result so far: 165.0
Subtract 2465 from 2829 to get 364.
Take the next digit (0) from the dividend and append it to 364, then repeat: 3640 / 493

Moving on to step 6:
493 goes into 3640 7 times with a remainder of 189.
Write down 7 as next digit of the result. 
Result so far: 1657.0
Deduct 3451 from 3640 and we're left with 189.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1890, and continue the process.

Step 7:
493 can be fit into 1890 3 times, resulting in a remainder of 411.
The number 3 becomes the next digit in our result. 
Result so far: 1657.3
Subtracting 1479 from 1890 leaves us with 411.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4110, and continue the process.

On to step 8:
If we divide 4110 by 493, we get 8 and a remainder of 166.
Write down 8 as next digit of the result. 
Result so far: 1657.38
Subtract 3944 from 4110 to get 166.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1660, and continue the process.

Advancing to step 9:
When dividing 1660 by 493, we get 3 with a remainder of 181.
Write down 3 as next digit of the result. 
Result so far: 1657.383
The remainder is 181 after subtracting 1479 from 1660.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1810, and continue the process.

Let's proceed to step 10:
493 goes into 1810 3 times with a remainder of 331.
Use 3 as the next digit of our solution. 
Result so far: 1657.3833
Subtract 1479 from 1810 to get 331.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3310, and continue the process.

The final outcome is 1657.3833, with a leftover of 0.00331.