What is the sum of 1 to 50?

1 + 50 2 + 49 3 + 48 (I have omitted the pairs in between) 25 + 26 All pairs sum to 51 25 pairs Therefore the sum total is 25*51, 1275. read more

All odd numbers have the form 2x + 1, where x is an integer. Another way of looking at this is that every odd number is an even number plus 1.. So lets take five odd numbers, 2v+1, 2w+1, 2x+1, 2y+1, and 2z+1, where v, w, x, y, and z are distinct integers. Adding them together we get:. (2v+1) + (2w+1) + (2x+1) + (2y+1) + (2z+1). read more

5,4,3,2,1 Now write them one on top of the other 1,2,3,4,5 5,4,3,2,1 If you add those two lists, column by column, each column has a total of 6. 5+1, 4+2, 3+3 etc. And since it was the numbers 1-5, there are 5 columns. read more