83878 ÷ 7 = 11982 R4
We're going to perform division on 83878 with 7 as the divisor.

Step 1:
7 goes into 8 1 times with a remainder of 1.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 7 from 8 to get 1.
Bring next digit (3) of the dividend behind the 1 and repeat the process: 13 / 7

Step 2:
7 goes into 13 1 times with a remainder of 6.
Write down 1 as next digit of of the result. 
Result so far: 11
Subtract 7 from 13 to get 6.
Bring next digit (8) of the dividend behind the 6 and repeat the process: 68 / 7

Step 3:
7 goes into 68 9 times with a remainder of 5.
Write down 9 as next digit of of the result. 
Result so far: 119
Subtract 63 from 68 to get 5.
Bring next digit (7) of the dividend behind the 5 and repeat the process: 57 / 7

Step 4:
7 goes into 57 8 times with a remainder of 1.
Write down 8 as next digit of of the result. 
Result so far: 1198
Subtract 56 from 57 to get 1.
Bring next digit (8) of the dividend behind the 1 and repeat the process: 18 / 7

Step 5:
7 goes into 18 2 times with a remainder of 4.
Write down 2 as next digit of of the result. 
Result so far: 11982
Subtract 14 from 18 to get 4.

The final result is 11982 with a remainder of 4.