778394 ÷ 21 
We're looking to find how many times 21 goes into 778394.

Advancing to step 1:
21 can be fit into 7 0 times, resulting in a remainder of 7.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 7 and we're left with 7.
Append the next digit (7) from the dividend to 7 and continue with: 77 / 21

On to step 2:
21 goes into 77 3 times with a remainder of 14.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
If we take 63 away from 77, we end up with 14.
Grab the next digit (8) from the dividend, add it to 14, then carry on: 148 / 21

Step 3:
If we divide 148 by 21, we get 7 and a remainder of 1.
Record the quotient 7 as the next digit in the result. 
Result so far: 37.0
Subtract 147 from 148 to get 1.
Bring next digit (3) of the dividend behind the 1 and repeat the process: 13 / 21

Let's proceed to step 4:
13 divided by 21 is 0 with a remainder of 13.
Record the quotient 0 as the next digit in the result. 
Result so far: 370.0
Subtract 0 from 13 to get 13.
Fetch the next digit (9) from the dividend, attach it to 13 and continue: 139 / 21

Let's proceed to step 5:
139 divided by 21 is 6 with a remainder of 13.
The number 6 becomes the next digit in our result. 
Result so far: 3706.0
If we subtract 126 from 139, we get 13.
Grab the next digit (4) from the dividend, add it to 13, then carry on: 134 / 21

Advancing to step 6:
When dividing 134 by 21, we get 6 with a remainder of 8.
The next digit of our result is 6. 
Result so far: 37066.0
Subtracting 126 from 134 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.

Going ahead to step 7:
21 can be fit into 80 3 times, resulting in a remainder of 17.
The number 3 becomes the next digit in our result. 
Result so far: 37066.3
Subtracting 63 from 80 leaves us with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Advancing to step 8:
170 divided by 21 is 8 with a remainder of 2.
Use 8 as the next digit of our solution. 
Result so far: 37066.38
Subtracting 168 from 170 leaves us with 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 9:
21 can be fit into 20 0 times, resulting in a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 37066.38
If we subtract 0 from 20, we get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 10:
If we divide 200 by 21, we get 9 and a remainder of 11.
Record the quotient 9 as the next digit in the result. 
Result so far: 37066.3809
Deduct 189 from 200 and we're left 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.

Advancing to step 11:
21 goes into 110 5 times with a remainder of 5.
Write down 5 as next digit of the result. 
Result so far: 37066.38095
Deduct 105 from 110 and we're left with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Advancing to step 12:
21 goes into 50 2 times with a remainder of 8.
Record the quotient 2 as the next digit in the result. 
Result so far: 37066.380952
Subtracting 42 from 50 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.

Moving on to step 13:
The number 21 fits into 80 3 times, leaving a remainder of 17.
Write down 3 as next digit of the result. 
Result so far: 37066.3809523
Subtracting 63 from 80 leaves us with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Let's proceed to step 14:
When dividing 170 by 21, we get 8 with a remainder of 2.
Write down 8 as next digit of the result. 
Result so far: 37066.38095238
Subtract 168 from 170 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.

The final outcome is 37066.38095238, with a leftover of 2e-09.