21473 ÷ 42 
We're looking to find how many times 42 goes into 21473.

Step 1:
The number 42 fits into 2 0 times, leaving a remainder of 2.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Grab the next digit (1) from the dividend, add it to 2, then carry on: 21 / 42

On to step 2:
42 goes into 21 0 times with a remainder of 21.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 21 after subtracting 0 from 21.
Take the next digit (4) from the dividend and append it to 21, then repeat: 214 / 42

On to step 3:
If we divide 214 by 42, we get 5 and a remainder of 4.
Use 5 as the next digit of our solution. 
Result so far: 5.0
If we take 210 away from 214, we end up with 4.
Take the next digit (7) from the dividend and append it to 4, then repeat: 47 / 42

Advancing to step 4:
If we divide 47 by 42, we get 1 and a remainder of 5.
Use 1 as the next digit of our solution. 
Result so far: 51.0
Subtracting 42 from 47 leaves us with 5.
Bring next digit (3) of the dividend behind the 5 and repeat the process: 53 / 42

Moving on to step 5:
42 goes into 53 1 times with a remainder of 11.
Put 1 as the next digit of the answer. 
Result so far: 511.0
If we take 42 away from 53, we end up with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Moving on to step 6:
The number 42 fits into 110 2 times, leaving a remainder of 26.
Record the quotient 2 as the next digit in the result. 
Result so far: 511.2
If we subtract 84 from 110, we get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Moving on to step 7:
42 goes into 260 6 times with a remainder of 8.
Write down 6 as next digit of the result. 
Result so far: 511.26
Subtracting 252 from 260 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Advancing to step 8:
The number 42 fits into 80 1 times, leaving a remainder of 38.
The number 1 becomes the next digit in our result. 
Result so far: 511.261
Deduct 42 from 80 and we're left with 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Let's proceed to step 9:
When dividing 380 by 42, we get 9 with a remainder of 2.
The number 9 becomes the next digit in our result. 
Result so far: 511.2619
Subtract 378 from 380 to get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Advancing to step 10:
42 can be fit into 20 0 times, resulting in a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 511.2619
The remainder is 20 after subtracting 0 from 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 11:
42 goes into 200 4 times with a remainder of 32.
Write down 4 as next digit of the result. 
Result so far: 511.261904
Subtracting 168 from 200 leaves us with 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Going ahead to step 12:
If we divide 320 by 42, we get 7 and a remainder of 26.
The next digit of our result is 7. 
Result so far: 511.2619047
If we take 294 away from 320, we end up with 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Going ahead to step 13:
When dividing 260 by 42, we get 6 with a remainder of 8.
Use 6 as the next digit of our solution. 
Result so far: 511.26190476
Deduct 252 from 260 and we're left with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

After the division, we end up with 511.26190476 and a remainder of 8e-09.