Question

If we add two consecutive triangular numbers, then we get _________.

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

Answer 1

The correct option is C square numbers

A triangular number counts objects arranged in an equilateral triangle. If we add two consecutive triangular numbers, we will get square numbers.

Set of triangular numbers is listed below:
{0,1,3,6,10,15,21,...}

Sum of two consecutive triangular numbers give a square number. For example:
$6+10=16=4^2$