Theory:

Predecessor and successor of an integer:
 
Let us first recall the successor and predecessor.
The successor of any number is adding \(1\) to the given number.
 
The predecessor of any number is subtracting \(1\) to the given number
We can easily found predecessor and successor using number line.
1. To find the predecessor of any number, move \(1\) unit to the left side of that number.
 
2. To find the successor of any number, move \(1\) unit to the right side of that number.
Example:
1. Find the predecessor of \(-1\).
 
Move \(1\) unit to the left side of \(-1\).
 
numberline4.PNG
 
The predecessor of \(-1\) is \(-2\).
 
 
2. Find the predecessor of \(1\).
 
Move \(1\) unit to the left side of \(1\).
 
numberline6.PNG
 
The predecessor of \(1\) is \(0\).
 
 
3. Find the successor of \(2\).
 
Move \(1\) unit to the right side of \(2\).
 
numberline3.PNG
 
The successor of \(2\) is \(3\).
 
 
4. Find the successor of \(-5\).
 
Move \(1\) unit to the right side of \(-5\).
 
numberline5.PNG
 
The successor of \(-5\) is \(-4\).