AMC10 2014 A

AMC10 2014 A · Q10

AMC10 2014 A · Q10. It mainly tests Averages (mean).

Five positive consecutive integers starting with $a$ have average $b$. What is the average of 5 consecutive integers that start with $b$?

以 $a$ 开头的五个正连续整数的平均数为 $b$。以 $b$ 开头的 5 个连续整数的平均数是多少？

(A) $a + 3$ $a + 3$

(B) $a + 4$ $a + 4$

(D) $a + 6$ $a + 6$

(E) $a + 7$ $a + 7$

Answer

Correct choice: (B)

正确答案：（B）

Solution

The five consecutive integers starting with $a$ are $a, a + 1, a + 2, a + 3,$ and $a + 4$. Their average is $a + 2 = b$. The average of five consecutive integers starting with $b$ is $b + 2 = a + 4$.

以 $a$ 开头的五个连续整数为 $a, a + 1, a + 2, a + 3,$ 和 $a + 4$。它们的平均数为 $a + 2 = b$。以 $b$ 开头的五个连续整数的平均数为 $b + 2 = a + 4$。

Topics

AR.006 Averages (mean)