Q. Can you find a quick and elegant way to add the numbers from 1 to 28 ?
In other words, what is the sum you obtain in the following case:
1 + 2 + 3 + ....... + 28 =?


Answer
406

Solution:
Here's an elegant way:
1 + 28 = 29
2 + 27 = 29
3 + 26 = 29
.....................
.....................
14 + 15 = 29
Adding the above equations gives
1 + 2 + 3 + ....... + 28 = 14 × 29 = 406