The average of all positive even integers less than or equal to 40 is___.
Correct Answer: 21
Solution and Explanation
To find the average of all positive even integers less than or equal to 40, we first identify these numbers: 2, 4, 6, ..., 40. This sequence is an arithmetic sequence where: First term (a1) = 2, Last term (an) = 40, Common difference (d) = 2. To find the number of terms (n), use the formula for the n-th term of an arithmetic sequence: an = a1 + (n-1)×d. The average of an arithmetic sequence can be calculated by the formula: Average = (a1 + an) / 2. Thus, the average of all positive even integers less than or equal to 40 is 21 |
Top Questions on Average
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