Question

If n is an even number, then the product of its successor and predecessor
(a) is an even natural number (b) is an odd natural number
(c) can be even or odd (d) None of these

Answer 1

Here, n is an even number.
Successor of n = n + 1
Predecessor of n = n − 1
Product = (n + 1) $\text{×}$ (n − 1) = odd $\text{×}$ odd = odd
Thus, the product of the successor and the predecessor of n is an odd natural number.
Hence, the correct option is (b).