题库搜索>问题求解PS-13349
In the first week of the year, Nancy saved $1. In each of the next 51 weeks, she saved $1 more than she had saved in the previous week. What was the total amount that Nancy saved during the 52 weeks?
分析A选项
分析B选项
分析C选项
分析D选项
分析E选项
第一周:1刀
第二周:1刀+1刀
第三周:1刀+1刀+1刀
所以低52周要存:52刀
所以这52周总共存的钱应该是:1+2+3+.....+52=(n(n+1))/2=1378
借我借我一双慧眼吧
一定要记好数列求和公式:n个数相加=(n(n+1))/2
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