27129 ÷ 7 = 3875 R4
We're going to perform division on 27129 with 7 as the divisor.

Step 1:
7 goes into 2 0 times with a remainder of 2.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 2 to get 2.
Bring next digit (7) of the dividend behind the 2 and repeat the process: 27 / 7

Step 2:
7 goes into 27 3 times with a remainder of 6.
Write down 3 as next digit of of the result. 
Result so far: 3
Subtract 21 from 27 to get 6.
Bring next digit (1) of the dividend behind the 6 and repeat the process: 61 / 7

Step 3:
7 goes into 61 8 times with a remainder of 5.
Write down 8 as next digit of of the result. 
Result so far: 38
Subtract 56 from 61 to get 5.
Bring next digit (2) of the dividend behind the 5 and repeat the process: 52 / 7

Step 4:
7 goes into 52 7 times with a remainder of 3.
Write down 7 as next digit of of the result. 
Result so far: 387
Subtract 49 from 52 to get 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 7

Step 5:
7 goes into 39 5 times with a remainder of 4.
Write down 5 as next digit of of the result. 
Result so far: 3875
Subtract 35 from 39 to get 4.

The final result is 3875 with a remainder of 4.