77517518 ÷ 172 
We want to figure out the number of times 77517518 can be divided by 172.

Going ahead to step 1:
172 can be fit into 7 0 times, resulting in a remainder of 7.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 7 to get 7.
Fetch the next digit (7) from the dividend, attach it to 7 and continue: 77 / 172

Step 2:
172 can be fit into 77 0 times, resulting in a remainder of 77.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 77, we get 77.
Include the next digit (5) from the dividend after 77, then repeat: 775 / 172

Let's proceed to step 3:
172 can be fit into 775 4 times, resulting in a remainder of 87.
Use 4 as the next digit of our solution. 
Result so far: 4.0
Subtracting 688 from 775 leaves us with 87.
Grab the next digit (1) from the dividend, add it to 87, then carry on: 871 / 172

Moving on to step 4:
172 can be fit into 871 5 times, resulting in a remainder of 11.
Write down 5 as next digit of the result. 
Result so far: 45.0
Subtracting 860 from 871 leaves us with 11.
Take the next digit (7) from the dividend and append it to 11, then repeat: 117 / 172

Going ahead to step 5:
The number 172 fits into 117 0 times, leaving a remainder of 117.
Use 0 as the next digit of our solution. 
Result so far: 450.0
Deduct 0 from 117 and we're left with 117.
Include the next digit (5) from the dividend after 117, then repeat: 1175 / 172

Step 6:
172 can be fit into 1175 6 times, resulting in a remainder of 143.
Put 6 as the next digit of the answer. 
Result so far: 4506.0
If we subtract 1032 from 1175, we get 143.
Grab the next digit (1) from the dividend, add it to 143, then carry on: 1431 / 172

Moving on to step 7:
If we divide 1431 by 172, we get 8 and a remainder of 55.
Put 8 as the next digit of the answer. 
Result so far: 45068.0
If we subtract 1376 from 1431, we get 55.
Include the next digit (8) from the dividend after 55, then repeat: 558 / 172

Going ahead to step 8:
172 can be fit into 558 3 times, resulting in a remainder of 42.
The next digit of our result is 3. 
Result so far: 450683.0
Deduct 516 from 558 and we're left with 42.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

Let's proceed to step 9:
172 goes into 420 2 times with a remainder of 76.
Use 2 as the next digit of our solution. 
Result so far: 450683.2
Deduct 344 from 420 and we're left with 76.
Since there are no more digits in the dividend, we add a zero to the remainder making it 760, and continue the process.

Going ahead to step 10:
172 goes into 760 4 times with a remainder of 72.
Record the quotient 4 as the next digit in the result. 
Result so far: 450683.24
Deduct 688 from 760 and we're left with 72.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

Moving on to step 11:
If we divide 720 by 172, we get 4 and a remainder of 32.
The number 4 becomes the next digit in our result. 
Result so far: 450683.244
Deduct 688 from 720 and we're left 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.

The final outcome is 450683.244, with a leftover of 0.0032.