Question

The sum of the successor and predecessor of $100$ is

• A. $101$
• B. $199$
• C. $200$
• D. $111$

Answer 1

The correct option is C

$200$

Step 1: Successor and Predecessor

Successor

Successor is the term that comes right after a particular number or term or a value. Suppose, $n$ is a whole number, then the successor of $n$ is $n+1$. The other terminologies used for successor are next value.

Predecessor

A predecessor is a value that comes right before a particular value. Suppose a value is $x$, then the predecessor of $x$ will be $x–1$. Thus, to find the predecessor of any value we have to subtract the given value from $1$.

Step 2: Explanation for correct answer

Option (c): $200$

Predecessor refers to the number that just comes before a given number.

So, the predecessor of $100$ is $100-1=99$

Successor refers to the number that just comes after a given number.

So, the successor of $100$ is $100+1=101$

On addition of the predecessor and successor we get $99+101=200$.

Thus, option (c) is the correct answer.

Step 3: Explanation for incorrect answer

Option (a): $101$

Option (b): $199$

Option (d): $111$

By adding the predecessor and successor of $100$, we get $200$.

Thus, option (a), (b) and (d) are incorrect answers.

Hence, option (c) is the correct answer.