42123 divided by 8 
We want to divide 42123 by 8.

Step 1:
8 can be fit into 4 0 times, resulting in a remainder of 4.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 4 and we're left with 4.
Bring next digit (2) of the dividend behind the 4 and repeat the process: 42 / 8

On to step 2:
8 goes into 42 5 times with a remainder of 2.
The number 5 becomes the next digit in our result. 
Result so far: 5.0
If we take 40 away from 42, we end up with 2.
Take the next digit (1) from the dividend and append it to 2, then repeat: 21 / 8

Let's proceed to step 3:
When dividing 21 by 8, we get 2 with a remainder of 5.
Use 2 as the next digit of our solution. 
Result so far: 52.0
Subtract 16 from 21 to get 5.
Grab the next digit (2) from the dividend, add it to 5, then carry on: 52 / 8

On to step 4:
The number 8 fits into 52 6 times, leaving a remainder of 4.
Put 6 as the next digit of the answer. 
Result so far: 526.0
If we take 48 away from 52, we end up with 4.
Bring next digit (3) of the dividend behind the 4 and repeat the process: 43 / 8

Going ahead to step 5:
The number 8 fits into 43 5 times, leaving a remainder of 3.
Write down 5 as next digit of the result. 
Result so far: 5265.0
If we subtract 40 from 43, we get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

On to step 6:
8 goes into 30 3 times with a remainder of 6.
Record the quotient 3 as the next digit in the result. 
Result so far: 5265.3
The remainder is 6 after subtracting 24 from 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Step 7:
If we divide 60 by 8, we get 7 and a remainder of 4.
Use 7 as the next digit of our solution. 
Result so far: 5265.37
Subtracting 56 from 60 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 8:
If we divide 40 by 8, we get 5 and a remainder of 0.
Put 5 as the next digit of the answer. 
Result so far: 5265.375
Deduct 40 from 40 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.

Let's proceed to step 9:
8 can be fit into 0 0 times, resulting in a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 5265.375
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 10:
8 can be fit into 0 0 times, resulting in a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 5265.375
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

After the division, we end up with 5265.375 and a remainder of 0.0.