Question

By adding two consecutive triangular numbers, we get

• A. square numbers
• B. even numbers
• C. odd numbers

Answer 1

The correct option is A square numbers

Consider the triangular numbers 1, 3, 6, 10...
Now, if we add 1 and 3 we get 4.
Similarly, if we add 3 and 6 we get 9 and if we add 6 and 10 we get 16.
4, 9 and 16 are square numbers since,
4 = $2^2$
9 = $3^2$
16 = $4^2$