The sum of the first 15 positive odd numbers can be found using the formula for the sum of an arithmetic series. In this case, the first term (a) is 1, the common difference (d) is 2, and the number of terms (n) is 15.
The formula for the sum of an arithmetic series is Sn = (n/2)(2a + (n-1)d), where Sn represents the sum of the series.
Plugging in the values, we have:
Sn = (15/2)(2(1) + (15-1)(2))
= (15/2)(2 + 14(2))
= (15/2)(2 + 28)
= (15/2)(30)
= 225
Therefore, the sum of the first 15 positive odd numbers is 225.
Find the sum of first 15 positive old numbers
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