87188173 divided by 409 
We want to figure out the number of times 87188173 can be divided by 409.

Let's proceed to step 1:
409 goes into 8 0 times with a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Append the next digit (7) from the dividend to 8 and continue with: 87 / 409

Step 2:
87 divided by 409 is 0 with a remainder of 87.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 87 to get 87.
Grab the next digit (1) from the dividend, add it to 87, then carry on: 871 / 409

Going ahead to step 3:
871 divided by 409 is 2 with a remainder of 53.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
Deduct 818 from 871 and we're left with 53.
Append the next digit (8) from the dividend to 53 and continue with: 538 / 409

Going ahead to step 4:
When dividing 538 by 409, we get 1 with a remainder of 129.
Put 1 as the next digit of the answer. 
Result so far: 21.0
If we subtract 409 from 538, we get 129.
Include the next digit (8) from the dividend after 129, then repeat: 1298 / 409

Let's proceed to step 5:
The number 409 fits into 1298 3 times, leaving a remainder of 71.
The next digit of our result is 3. 
Result so far: 213.0
Deduct 1227 from 1298 and we're left with 71.
Fetch the next digit (1) from the dividend, attach it to 71 and continue: 711 / 409

Step 6:
711 divided by 409 is 1 with a remainder of 302.
Put 1 as the next digit of the answer. 
Result so far: 2131.0
The remainder is 302 after subtracting 409 from 711.
Grab the next digit (7) from the dividend, add it to 302, then carry on: 3027 / 409

On to step 7:
The number 409 fits into 3027 7 times, leaving a remainder of 164.
Put 7 as the next digit of the answer. 
Result so far: 21317.0
The remainder is 164 after subtracting 2863 from 3027.
Include the next digit (3) from the dividend after 164, then repeat: 1643 / 409

On to step 8:
409 goes into 1643 4 times with a remainder of 7.
Use 4 as the next digit of our solution. 
Result so far: 213174.0
Subtract 1636 from 1643 to get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Advancing to step 9:
409 goes into 70 0 times with a remainder of 70.
Use 0 as the next digit of our solution. 
Result so far: 213174.0
The remainder is 70 after subtracting 0 from 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Going ahead to step 10:
700 divided by 409 is 1 with a remainder of 291.
Use 1 as the next digit of our solution. 
Result so far: 213174.01
If we subtract 409 from 700, we get 291.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2910, and continue the process.

Step 11:
409 goes into 2910 7 times with a remainder of 47.
Use 7 as the next digit of our solution. 
Result so far: 213174.017
If we subtract 2863 from 2910, we get 47.
Since there are no more digits in the dividend, we add a zero to the remainder making it 470, and continue the process.

Let's proceed to step 12:
When dividing 470 by 409, we get 1 with a remainder of 61.
The next digit of our result is 1. 
Result so far: 213174.0171
If we subtract 409 from 470, we get 61.
Since there are no more digits in the dividend, we add a zero to the remainder making it 610, and continue the process.

Let's proceed to step 13:
When dividing 610 by 409, we get 1 with a remainder of 201.
The number 1 becomes the next digit in our result. 
Result so far: 213174.01711
If we subtract 409 from 610, we get 201.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2010, and continue the process.

Our division results in 213174.01711 with a remaining 0.000201.