Re: [計量] 請教幾題計量
※ 引述《tako1016 (Tako)》之銘言：
: Given that a vending machine dispenses gumballs in a regularly repeating
: cycle of ten different colors. If a quarter buy 3 gumballs, what is the
: minium amount of money that must be spent before three gumballs of the
: same color are dispensed? ans: 5 dollars and 1 quarter
請見9282篇。#1A-Y9YLG (GRE)
: A measurement 1.21 is 1.5 standard variation below the mean and 1.75 is
: 3 standard variation over the mean , ask the mean? ans: 1.39
刻度1.21是平均值之下 1.5個標準差的位置，刻度1.75則是平均值之上 3個標準
差的位置。已知標準差都一樣，所以 1.21 ~ 1.75的距離相當於 1.5 + 3 = 4.5
個標準差長度。按照比例計算後得到平均值在1.39。
: 看不太懂這題在問甚麼?
: Two names Johnson and Jones are given. If one letter is picked from both
: names simultaneously at random, what is the probability that the letters
: picked will be the same? ans: 6/35
相同的字母有 J、 o、 n、 s
J相同：(1/7)*(1/5) = 1/35
o相同：(2/7)*(1/5) = 2/35
n相同：(2/7)*(1/5) = 2/35
s相同：(1/7)*(1/5) = 1/35
合計：6/35
: 在兩個禮拜就要上戰場了 麻煩幫忙解題了
考試加油！
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