5661 ÷ 3 = 1887 R0
We're going to perform division on 5661 with 3 as the divisor.

Step 1:
3 goes into 5 1 times with a remainder of 2.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 3 from 5 to get 2.
Bring next digit (6) of the dividend behind the 2 and repeat the process: 26 / 3

Step 2:
3 goes into 26 8 times with a remainder of 2.
Write down 8 as next digit of of the result. 
Result so far: 18
Subtract 24 from 26 to get 2.
Bring next digit (6) of the dividend behind the 2 and repeat the process: 26 / 3

Step 3:
3 goes into 26 8 times with a remainder of 2.
Write down 8 as next digit of of the result. 
Result so far: 188
Subtract 24 from 26 to get 2.
Bring next digit (1) of the dividend behind the 2 and repeat the process: 21 / 3

Step 4:
3 goes into 21 7 times with a remainder of 0.
Write down 7 as next digit of of the result. 
Result so far: 1887
Subtract 21 from 21 to get 0.

The final result is 1887 with a remainder of 0.