We divide 53151978 by 420
Our goal is to divide 53151978 by 420.

Step 1:
420 can be fit into 5 0 times, resulting in a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 5, we end up with 5.
Append the next digit (3) from the dividend to 5 and continue with: 53 / 420

Going ahead to step 2:
If we divide 53 by 420, we get 0 and a remainder of 53.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 53 to get 53.
Include the next digit (1) from the dividend after 53, then repeat: 531 / 420

Let's proceed to step 3:
531 divided by 420 is 1 with a remainder of 111.
The next digit of our result is 1. 
Result so far: 1.0
The remainder is 111 after subtracting 420 from 531.
Grab the next digit (5) from the dividend, add it to 111, then carry on: 1115 / 420

Let's proceed to step 4:
When dividing 1115 by 420, we get 2 with a remainder of 275.
Record the quotient 2 as the next digit in the result. 
Result so far: 12.0
Deduct 840 from 1115 and we're left with 275.
Append the next digit (1) from the dividend to 275 and continue with: 2751 / 420

Moving on to step 5:
When dividing 2751 by 420, we get 6 with a remainder of 231.
Use 6 as the next digit of our solution. 
Result so far: 126.0
The remainder is 231 after subtracting 2520 from 2751.
Grab the next digit (9) from the dividend, add it to 231, then carry on: 2319 / 420

Advancing to step 6:
The number 420 fits into 2319 5 times, leaving a remainder of 219.
Write down 5 as next digit of the result. 
Result so far: 1265.0
Subtracting 2100 from 2319 leaves us with 219.
Include the next digit (7) from the dividend after 219, then repeat: 2197 / 420

Let's proceed to step 7:
2197 divided by 420 is 5 with a remainder of 97.
Write down 5 as next digit of the result. 
Result so far: 12655.0
If we take 2100 away from 2197, we end up with 97.
Grab the next digit (8) from the dividend, add it to 97, then carry on: 978 / 420

Advancing to step 8:
When dividing 978 by 420, we get 2 with a remainder of 138.
Record the quotient 2 as the next digit in the result. 
Result so far: 126552.0
If we take 840 away from 978, we end up with 138.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1380, and continue the process.

Moving on to step 9:
When dividing 1380 by 420, we get 3 with a remainder of 120.
Record the quotient 3 as the next digit in the result. 
Result so far: 126552.3
If we subtract 1260 from 1380, we get 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1200, and continue the process.

Advancing to step 10:
1200 divided by 420 is 2 with a remainder of 360.
The next digit of our result is 2. 
Result so far: 126552.32
If we take 840 away from 1200, we end up with 360.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3600, and continue the process.

Let's proceed to step 11:
If we divide 3600 by 420, we get 8 and a remainder of 240.
Put 8 as the next digit of the answer. 
Result so far: 126552.328
The remainder is 240 after subtracting 3360 from 3600.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2400, and continue the process.

Moving on to step 12:
When dividing 2400 by 420, we get 5 with a remainder of 300.
Record the quotient 5 as the next digit in the result. 
Result so far: 126552.3285
If we subtract 2100 from 2400, we get 300.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3000, and continue the process.

Let's proceed to step 13:
420 can be fit into 3000 7 times, resulting in a remainder of 60.
The number 7 becomes the next digit in our result. 
Result so far: 126552.32857
If we subtract 2940 from 3000, we get 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

Going ahead to step 14:
The number 420 fits into 600 1 times, leaving a remainder of 180.
The next digit of our result is 1. 
Result so far: 126552.328571
If we take 420 away from 600, we end up with 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1800, and continue the process.

Going ahead to step 15:
If we divide 1800 by 420, we get 4 and a remainder of 120.
Write down 4 as next digit of the result. 
Result so far: 126552.3285714
If we take 1680 away from 1800, we end up with 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1200, and continue the process.

On to step 16:
420 goes into 1200 2 times with a remainder of 360.
The number 2 becomes the next digit in our result. 
Result so far: 126552.32857142
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.

The final outcome is 126552.32857142, with a leftover of 3.6e-07.