78351 ÷ 5 = 15670 R1
Alright, let's work through the division of 78351 by 5 step by step.

Step 1:
5 goes into 7 1 times with a remainder of 2.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 5 from 7 to get 2.
Bring next digit (8) of the dividend behind the 2 and repeat the process: 28 / 5

Step 2:
5 goes into 28 5 times with a remainder of 3.
Write down 5 as next digit of of the result. 
Result so far: 15
Subtract 25 from 28 to get 3.
Bring next digit (3) of the dividend behind the 3 and repeat the process: 33 / 5

Step 3:
5 goes into 33 6 times with a remainder of 3.
Write down 6 as next digit of of the result. 
Result so far: 156
Subtract 30 from 33 to get 3.
Bring next digit (5) of the dividend behind the 3 and repeat the process: 35 / 5

Step 4:
5 goes into 35 7 times with a remainder of 0.
Write down 7 as next digit of of the result. 
Result so far: 1567
Subtract 35 from 35 to get 0.
Bring next digit (1) of the dividend behind the 0 and repeat the process: 1 / 5

Step 5:
5 goes into 1 0 times with a remainder of 1.
Write down 0 as next digit of of the result. 
Result so far: 15670
Subtract 0 from 1 to get 1.

The final result is 15670 with a remainder of 1.