For any positive integer n, the sum of the first n positive integers equals ~$\frac{n\left ( n+1 \right )}{2}$~. What is the sum of all the even integers between 99 and 301?
10,100
20,200
22,650
40,200
45,150
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注意:偶数的个数是(300-100)÷2+1!!!
注意:偶数的个数是(300-100)÷2+1!!!
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