We divide 58155759 by 21
The aim is to understand the frequency of 21 in 58155759.

Going ahead to step 1:
5 divided by 21 is 0 with a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 5 and we're left with 5.
Fetch the next digit (8) from the dividend, attach it to 5 and continue: 58 / 21

Let's proceed to step 2:
58 divided by 21 is 2 with a remainder of 16.
The next digit of our result is 2. 
Result so far: 2.0
If we subtract 42 from 58, we get 16.
Take the next digit (1) from the dividend and append it to 16, then repeat: 161 / 21

Moving on to step 3:
21 can be fit into 161 7 times, resulting in a remainder of 14.
Use 7 as the next digit of our solution. 
Result so far: 27.0
If we take 147 away from 161, we end up with 14.
Take the next digit (5) from the dividend and append it to 14, then repeat: 145 / 21

Step 4:
When dividing 145 by 21, we get 6 with a remainder of 19.
Write down 6 as next digit of the result. 
Result so far: 276.0
If we take 126 away from 145, we end up with 19.
Grab the next digit (5) from the dividend, add it to 19, then carry on: 195 / 21

Going ahead to step 5:
195 divided by 21 is 9 with a remainder of 6.
Put 9 as the next digit of the answer. 
Result so far: 2769.0
Subtract 189 from 195 to get 6.
Include the next digit (7) from the dividend after 6, then repeat: 67 / 21

Moving on to step 6:
21 goes into 67 3 times with a remainder of 4.
Record the quotient 3 as the next digit in the result. 
Result so far: 27693.0
Subtract 63 from 67 to get 4.
Grab the next digit (5) from the dividend, add it to 4, then carry on: 45 / 21

Going ahead to step 7:
21 can be fit into 45 2 times, resulting in a remainder of 3.
The number 2 becomes the next digit in our result. 
Result so far: 276932.0
Deduct 42 from 45 and we're left with 3.
Append the next digit (9) from the dividend to 3 and continue with: 39 / 21

On to step 8:
If we divide 39 by 21, we get 1 and a remainder of 18.
The number 1 becomes the next digit in our result. 
Result so far: 2769321.0
If we take 21 away from 39, we end up with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Step 9:
180 divided by 21 is 8 with a remainder of 12.
Record the quotient 8 as the next digit in the result. 
Result so far: 2769321.8
If we subtract 168 from 180, we get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Advancing to step 10:
120 divided by 21 is 5 with a remainder of 15.
The next digit of our result is 5. 
Result so far: 2769321.85
If we take 105 away from 120, we end up with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Going ahead to step 11:
21 goes into 150 7 times with a remainder of 3.
Write down 7 as next digit of the result. 
Result so far: 2769321.857
Subtracting 147 from 150 leaves us with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Moving on to step 12:
If we divide 30 by 21, we get 1 and a remainder of 9.
Use 1 as the next digit of our solution. 
Result so far: 2769321.8571
If we subtract 21 from 30, we get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Step 13:
21 goes into 90 4 times with a remainder of 6.
Put 4 as the next digit of the answer. 
Result so far: 2769321.85714
Subtracting 84 from 90 leaves us with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

On to step 14:
21 goes into 60 2 times with a remainder of 18.
Write down 2 as next digit of the result. 
Result so far: 2769321.857142
Subtracting 42 from 60 leaves us with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Advancing to step 15:
If we divide 180 by 21, we get 8 and a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 2769321.8571428
The remainder is 12 after subtracting 168 from 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 16:
21 goes into 120 5 times with a remainder of 15.
The next digit of our result is 5. 
Result so far: 2769321.85714285
Deduct 105 from 120 and we're left with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

After the division, we end up with 2769321.85714285 and a remainder of 1.5e-08.