Math

1+3+5...+259

Asked by
Last updated by anonymous
1 Answers
Log in to answer
add odd numbers together 1,3,5.....129,131....255,257,259. Look at the first and last numbers: 1 + 259 Then the next two: 3 + 257 Then the next two 5 + 255 etc. 129 + 131 They all add up to 259 and you have 65 pairs. Answer: sum = 65*260 = 16900