We look at the division of 75870801 by 3 
The aim is to understand the frequency of 3 in 75870801.

Step 1:
3 goes into 7 2 times with a remainder of 1.
The next digit of our result is 2. 
Result so far: 2.0
Subtracting 6 from 7 leaves us with 1.
Bring next digit (5) of the dividend behind the 1 and repeat the process: 15 / 3

Let's proceed to step 2:
The number 3 fits into 15 5 times, leaving a remainder of 0.
Record the quotient 5 as the next digit in the result. 
Result so far: 25.0
If we take 15 away from 15, we end up with 0.
Include the next digit (8) from the dividend after 0, then repeat: 8 / 3

Let's proceed to step 3:
3 can be fit into 8 2 times, resulting in a remainder of 2.
The number 2 becomes the next digit in our result. 
Result so far: 252.0
The remainder is 2 after subtracting 6 from 8.
Include the next digit (7) from the dividend after 2, then repeat: 27 / 3

Step 4:
3 goes into 27 9 times with a remainder of 0.
Put 9 as the next digit of the answer. 
Result so far: 2529.0
Deduct 27 from 27 and we're left with 0.
Grab the next digit (0) from the dividend, add it to 0, then carry on: 0 / 3

On to step 5:
When dividing 0 by 3, we get 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 25290.0
Subtracting 0 from 0 leaves us with 0.
Include the next digit (8) from the dividend after 0, then repeat: 8 / 3

On to step 6:
The number 3 fits into 8 2 times, leaving a remainder of 2.
Use 2 as the next digit of our solution. 
Result so far: 252902.0
Subtract 6 from 8 to get 2.
Grab the next digit (0) from the dividend, add it to 2, then carry on: 20 / 3

On to step 7:
If we divide 20 by 3, we get 6 and a remainder of 2.
The next digit of our result is 6. 
Result so far: 2529026.0
Subtract 18 from 20 to get 2.
Take the next digit (1) from the dividend and append it to 2, then repeat: 21 / 3

Moving on to step 8:
3 can be fit into 21 7 times, resulting in a remainder of 0.
The number 7 becomes the next digit in our result. 
Result so far: 25290267.0
Deduct 21 from 21 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Going ahead to step 9:
3 can be fit into 0 0 times, resulting in a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 25290267.0
If we take 0 away from 0, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Going ahead to step 10:
3 can be fit into 0 0 times, resulting in a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 25290267.0
If we take 0 away from 0, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final result is 25290267.0 with a remainder of 0.0.