[計量] pp上的DS

看板GMAT (GMAT入學考試)作者 (無)時間16年前 (2009/11/27 01:05), 編輯推噓1(101)
留言2則, 1人參與, 最新討論串1/1
1.During an experiment,some water was removed from each of 6 water tanks.If the standard deviation of the volumes of water in the tanks at the beginning of the experiment was 10 gallons,what was the standard deviation of the volumes of water in the tanks at the end of the experiment? (1)For each tank,30 percent of the volume of water was in the tank at the beginning of the experiment was removed during the experiment. (2)The average (arithemetic mean) volume of water in the tanks at the end of the experiment was 63 gallons. 答案是A 其實我不是很懂題目的意思~~但應該是利用S.D概念吧...... 2.If p is a prime number greater than 2,what is the value of p? (1)There are a total of 100 prime numbers between 1 and p+1. (2)There are a total of p prime numbers between i and 3912. 答案是D 謝謝 謝謝 謝謝 -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 61.224.24.102

11/27 08:20, , 1F
第一題,因為所有的tank都減少30%且原始volume相同,故標準
11/27 08:20, 1F

11/27 08:20, , 2F
差不變,仍然是10
11/27 08:20, 2F
文章代碼(AID): #1B3hLmZx (GMAT)
文章代碼(AID): #1B3hLmZx (GMAT)