Successor and predecessor are also known as after number and before number respectively.
Predecessor : As we know that predecessor means before number. There are two methods to find the before number.
1) Say the counting numbers and stop at the number up to which you have to find the before number. Example : Find the before number of 9 .
Say 1,2,3,4,5,6,7,8,9 so before 9 we said 8 so 8 is the predecessor of 9.
2) If you want to find the predecessor of given number then subtract 1 from the given number.
Example : 1) Predecessor of 9 is 9 -1 = 8
2) Predecessor of 13 is 13 – 1 = 12
3) Predecessor of 20 is 20 -1 = 19 Note : There is no predecessor of whole number zero. Successor There are two methods to find the successor of the given number.
1) Say the counting numbers and stop at the given number and say the next number that will be the successor of the given number. Example : Find the successor of 12 .
Say 1,2,3,4,5,6,7,8,9,10,11,12 and then the next number is 13 so 13 is the successor of 12.
But this method is used only for small numbers.
2) For big numbers the successor is the number obtained by adding 1 to it. Example : a) The successor of 13 is 13 + 1= 14.So 14 is the successor of 13.
b) The successor of 0 is 0 + 1 = 1.
c) Successor of 7 is 7 + 1 = 8
d) Successor of 56 is 56 + 1= 57.