We're dividing 15221222 by 649 
We want to figure out the number of times 15221222 can be divided by 649.

Step 1:
649 can be fit into 1 0 times, resulting in a remainder of 1.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 1 and we're left with 1.
Fetch the next digit (5) from the dividend, attach it to 1 and continue: 15 / 649

Advancing to step 2:
649 can be fit into 15 0 times, resulting in a remainder of 15.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 15 to get 15.
Grab the next digit (2) from the dividend, add it to 15, then carry on: 152 / 649

On to step 3:
If we divide 152 by 649, we get 0 and a remainder of 152.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 152 and we're left with 152.
Append the next digit (2) from the dividend to 152 and continue with: 1522 / 649

Step 4:
1522 divided by 649 is 2 with a remainder of 224.
Write down 2 as next digit of the result. 
Result so far: 2.0
Subtracting 1298 from 1522 leaves us with 224.
Fetch the next digit (1) from the dividend, attach it to 224 and continue: 2241 / 649

Let's proceed to step 5:
649 can be fit into 2241 3 times, resulting in a remainder of 294.
Write down 3 as next digit of the result. 
Result so far: 23.0
Subtracting 1947 from 2241 leaves us with 294.
Append the next digit (2) from the dividend to 294 and continue with: 2942 / 649

Let's proceed to step 6:
The number 649 fits into 2942 4 times, leaving a remainder of 346.
Put 4 as the next digit of the answer. 
Result so far: 234.0
If we take 2596 away from 2942, we end up with 346.
Append the next digit (2) from the dividend to 346 and continue with: 3462 / 649

Step 7:
If we divide 3462 by 649, we get 5 and a remainder of 217.
The next digit of our result is 5. 
Result so far: 2345.0
Subtract 3245 from 3462 to get 217.
Take the next digit (2) from the dividend and append it to 217, then repeat: 2172 / 649

Advancing to step 8:
If we divide 2172 by 649, we get 3 and a remainder of 225.
The number 3 becomes the next digit in our result. 
Result so far: 23453.0
Deduct 1947 from 2172 and we're left with 225.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2250, and continue the process.

Step 9:
If we divide 2250 by 649, we get 3 and a remainder of 303.
The next digit of our result is 3. 
Result so far: 23453.3
Subtract 1947 from 2250 to get 303.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3030, and continue the process.

Going ahead to step 10:
When dividing 3030 by 649, we get 4 with a remainder of 434.
Put 4 as the next digit of the answer. 
Result so far: 23453.34
If we subtract 2596 from 3030, we get 434.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4340, and continue the process.

Let's proceed to step 11:
The number 649 fits into 4340 6 times, leaving a remainder of 446.
Write down 6 as next digit of the result. 
Result so far: 23453.346
The remainder is 446 after subtracting 3894 from 4340.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4460, and continue the process.

Moving on to step 12:
649 goes into 4460 6 times with a remainder of 566.
Record the quotient 6 as the next digit in the result. 
Result so far: 23453.3466
Subtracting 3894 from 4460 leaves us with 566.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5660, and continue the process.

The final outcome is 23453.3466, with a leftover of 0.00566.