1至100之间的奇数有:1,3,5,7,9,11,13,15,17 ,19, 21,23,25,27 ,29, 31,33,35,37,39,41,43,45,47,49,51,53,55,57,59,61,63,65,67,69 ,71,73 ,75,77,79, 81,83,85,87,89,91,93,95,97,99 。这些数加起来的和为2500
1至100之间的奇数有:1,3,5,7,9,11,13,15,17 ,19, 21,23,25,27 ,29, 31,33,35,37,39,41,43,45,47,49,51,53,55,57,59,61,63,65,67,69 ,71,73 ,75,77,79, 81,83,85,87,89,91,93,95,97,99 。这些数加起来的和为2500