99660 ÷ 4 = 24915 R0
We're going to perform division on 99660 with 4 as the divisor.

Step 1:
4 goes into 9 2 times with a remainder of 1.
Write down 2 as next digit of of the result. 
Result so far: 2
Subtract 8 from 9 to get 1.
Bring next digit (9) of the dividend behind the 1 and repeat the process: 19 / 4

Step 2:
4 goes into 19 4 times with a remainder of 3.
Write down 4 as next digit of of the result. 
Result so far: 24
Subtract 16 from 19 to get 3.
Bring next digit (6) of the dividend behind the 3 and repeat the process: 36 / 4

Step 3:
4 goes into 36 9 times with a remainder of 0.
Write down 9 as next digit of of the result. 
Result so far: 249
Subtract 36 from 36 to get 0.
Bring next digit (6) of the dividend behind the 0 and repeat the process: 6 / 4

Step 4:
4 goes into 6 1 times with a remainder of 2.
Write down 1 as next digit of of the result. 
Result so far: 2491
Subtract 4 from 6 to get 2.
Bring next digit (0) of the dividend behind the 2 and repeat the process: 20 / 4

Step 5:
4 goes into 20 5 times with a remainder of 0.
Write down 5 as next digit of of the result. 
Result so far: 24915
Subtract 20 from 20 to get 0.

The final result is 24915 with a remainder of 0.