We look at the division of 3673791 by 840 
The aim is to understand the frequency of 840 in 3673791.

Step 1:
When dividing 3 by 840, we get 0 with a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 3 leaves us with 3.
Bring next digit (6) of the dividend behind the 3 and repeat the process: 36 / 840

Going ahead to step 2:
The number 840 fits into 36 0 times, leaving a remainder of 36.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 36, we end up with 36.
Grab the next digit (7) from the dividend, add it to 36, then carry on: 367 / 840

Step 3:
When dividing 367 by 840, we get 0 with a remainder of 367.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 367, we end up with 367.
Append the next digit (3) from the dividend to 367 and continue with: 3673 / 840

On to step 4:
The number 840 fits into 3673 4 times, leaving a remainder of 313.
Record the quotient 4 as the next digit in the result. 
Result so far: 4.0
Subtracting 3360 from 3673 leaves us with 313.
Fetch the next digit (7) from the dividend, attach it to 313 and continue: 3137 / 840

Let's proceed to step 5:
840 can be fit into 3137 3 times, resulting in a remainder of 617.
Record the quotient 3 as the next digit in the result. 
Result so far: 43.0
Deduct 2520 from 3137 and we're left with 617.
Append the next digit (9) from the dividend to 617 and continue with: 6179 / 840

Let's proceed to step 6:
The number 840 fits into 6179 7 times, leaving a remainder of 299.
The number 7 becomes the next digit in our result. 
Result so far: 437.0
Subtract 5880 from 6179 to get 299.
Fetch the next digit (1) from the dividend, attach it to 299 and continue: 2991 / 840

Let's proceed to step 7:
When dividing 2991 by 840, we get 3 with a remainder of 471.
Put 3 as the next digit of the answer. 
Result so far: 4373.0
The remainder is 471 after subtracting 2520 from 2991.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4710, and continue the process.

Let's proceed to step 8:
If we divide 4710 by 840, we get 5 and a remainder of 510.
Put 5 as the next digit of the answer. 
Result so far: 4373.5
Subtract 4200 from 4710 to get 510.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5100, and continue the process.

Advancing to step 9:
840 can be fit into 5100 6 times, resulting in a remainder of 60.
Write down 6 as next digit of the result. 
Result so far: 4373.56
Subtracting 5040 from 5100 leaves us with 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

Let's proceed to step 10:
The number 840 fits into 600 0 times, leaving a remainder of 600.
The number 0 becomes the next digit in our result. 
Result so far: 4373.56
If we take 0 away from 600, we end up with 600.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6000, and continue the process.

Let's proceed to step 11:
840 can be fit into 6000 7 times, resulting in a remainder of 120.
The number 7 becomes the next digit in our result. 
Result so far: 4373.5607
The remainder is 120 after subtracting 5880 from 6000.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1200, and continue the process.

Step 12:
840 can be fit into 1200 1 times, resulting in a remainder of 360.
The number 1 becomes the next digit in our result. 
Result so far: 4373.56071
Subtract 840 from 1200 to get 360.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3600, and continue the process.

On to step 13:
840 can be fit into 3600 4 times, resulting in a remainder of 240.
Use 4 as the next digit of our solution. 
Result so far: 4373.560714
Subtracting 3360 from 3600 leaves us with 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2400, and continue the process.

Let's proceed to step 14:
When dividing 2400 by 840, we get 2 with a remainder of 720.
The next digit of our result is 2. 
Result so far: 4373.5607142
If we take 1680 away from 2400, we end up with 720.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7200, and continue the process.

Advancing to step 15:
When dividing 7200 by 840, we get 8 with a remainder of 480.
The next digit of our result is 8. 
Result so far: 4373.56071428
Subtracting 6720 from 7200 leaves us with 480.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4800, and continue the process.

After the division, we end up with 4373.56071428 and a remainder of 4.8e-07.