We look at the division of 99970933 by 644 
Let's see how many times 644 fits into 99970933.

Let's proceed to step 1:
644 can be fit into 9 0 times, resulting in a remainder of 9.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 9 and we're left with 9.
Append the next digit (9) from the dividend to 9 and continue with: 99 / 644

Advancing to step 2:
The number 644 fits into 99 0 times, leaving a remainder of 99.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 99 and we're left with 99.
Grab the next digit (9) from the dividend, add it to 99, then carry on: 999 / 644

On to step 3:
644 can be fit into 999 1 times, resulting in a remainder of 355.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
If we subtract 644 from 999, we get 355.
Bring next digit (7) of the dividend behind the 355 and repeat the process: 3557 / 644

On to step 4:
The number 644 fits into 3557 5 times, leaving a remainder of 337.
Use 5 as the next digit of our solution. 
Result so far: 15.0
The remainder is 337 after subtracting 3220 from 3557.
Append the next digit (0) from the dividend to 337 and continue with: 3370 / 644

Step 5:
644 can be fit into 3370 5 times, resulting in a remainder of 150.
Write down 5 as next digit of the result. 
Result so far: 155.0
Subtracting 3220 from 3370 leaves us with 150.
Bring next digit (9) of the dividend behind the 150 and repeat the process: 1509 / 644

Step 6:
644 can be fit into 1509 2 times, resulting in a remainder of 221.
Put 2 as the next digit of the answer. 
Result so far: 1552.0
Subtracting 1288 from 1509 leaves us with 221.
Bring next digit (3) of the dividend behind the 221 and repeat the process: 2213 / 644

Moving on to step 7:
If we divide 2213 by 644, we get 3 and a remainder of 281.
Write down 3 as next digit of the result. 
Result so far: 15523.0
Subtract 1932 from 2213 to get 281.
Bring next digit (3) of the dividend behind the 281 and repeat the process: 2813 / 644

Going ahead to step 8:
When dividing 2813 by 644, we get 4 with a remainder of 237.
Write down 4 as next digit of the result. 
Result so far: 155234.0
The remainder is 237 after subtracting 2576 from 2813.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2370, and continue the process.

Advancing to step 9:
If we divide 2370 by 644, we get 3 and a remainder of 438.
Write down 3 as next digit of the result. 
Result so far: 155234.3
Subtracting 1932 from 2370 leaves us with 438.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4380, and continue the process.

Moving on to step 10:
The number 644 fits into 4380 6 times, leaving a remainder of 516.
The next digit of our result is 6. 
Result so far: 155234.36
If we subtract 3864 from 4380, we get 516.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5160, and continue the process.

Going ahead to step 11:
When dividing 5160 by 644, we get 8 with a remainder of 8.
Put 8 as the next digit of the answer. 
Result so far: 155234.368
If we subtract 5152 from 5160, we get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Step 12:
If we divide 80 by 644, we get 0 and a remainder of 80.
The next digit of our result is 0. 
Result so far: 155234.368
If we subtract 0 from 80, we get 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Moving on to step 13:
644 can be fit into 800 1 times, resulting in a remainder of 156.
The next digit of our result is 1. 
Result so far: 155234.36801
The remainder is 156 after subtracting 644 from 800.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1560, and continue the process.

Let's proceed to step 14:
644 can be fit into 1560 2 times, resulting in a remainder of 272.
Put 2 as the next digit of the answer. 
Result so far: 155234.368012
Subtract 1288 from 1560 to get 272.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2720, and continue the process.

Step 15:
The number 644 fits into 2720 4 times, leaving a remainder of 144.
Write down 4 as next digit of the result. 
Result so far: 155234.3680124
Deduct 2576 from 2720 and we're left with 144.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1440, and continue the process.

Advancing to step 16:
644 can be fit into 1440 2 times, resulting in a remainder of 152.
Write down 2 as next digit of the result. 
Result so far: 155234.36801242
Deduct 1288 from 1440 and we're left with 152.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1520, and continue the process.

After the division, we end up with 155234.36801242 and a remainder of 1.52e-07.