→ dounts:B 無誤 10/10 14:36
→ dounts:而且不用帶 因為有兩數的比例和平均 就可以用比例平均求出 10/10 14:37
→ koala0416:謝謝D大 10/10 22:47
Q13
If the average (arithmetic mean) of the assessed values
of x houses is $212,000 and the average of the assessed
values of y other houses is $194,000, what is the average
of the assessed values of the x+y houses?
(1) x+y=36
(2) x=2y
GWD解答給的是C
但如果(2) 帶入21200X+19400Y/X+Y 不是直接有答案了嗎?
所以是B嗎? 還是有沒考慮到的地方 煩請高手解答 感謝
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