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2014年1月16日SAT官方每日一题---数学选择

  下面是2014年1月16日的SAT官方每日一题的内容,是关于数学方面的,题型是选择。SAT官方每日一题是collegeboard每天都会发布的题目,关于SAT考试的三个部分的各个题型。大家和无忧小编一起来看一下这个SAT官方每日一题吧。

  SAT官方每日一题之数学---选择:

  Mathematics > Standard Multiple Choice

  Read the following SAT test question and then click on a button to select your answer.

  If(absolute value of a) minus (absolute value of b) equals 5, which of the following could be true?

  (A)a equals 0

  (B)b equals 0

  (C)a equals b

  (D)a equals negative b

  (E)a equals 1

  The correct answer is B

  Explanation

  Ifb equals 0anda equals 5, then(absolute value of a) minus (absolute value of b) equals (absolute value of 5) minus (absolute value of 0) equals 5. Hence if(absolute value of a) minus (absolute value of b) equals 5, it could be true thatb equals 0.

  If(absolute value of a) minus (absolute value of b) equals 5, none of the other four statements could be true:

  Ifa equals 0, then(absolute value of a) minus (absolute value of b) equals 0 minus (absolute value of b) equals negative (absolute value of b). However, since(absolute value of b) is greater than or equal to 0, there is no value ofbfor whichnegative (absolute value of b) equals 5.

  Ifa equals b, then(absolute value of a) minus (absolute value of b) equals (absolute value of a) minus (absolute value of a) equals 0 does not equal 5.

  Ifa equals negative b, then(absolute value of a) minus (absolute value of b) equals (negative absolute value of b) minus (absolute value of b) equals (absolute value of b) minus (absolute value of b) equals 0 does not equal 5.

  Ifa equals 1, then(absolute value of a) minus (absolute value of b) equals (absolute value of 1) minus (absolute value of b) equals 1 minus (absolute value of b). However, since(absolute value of b) is greater than or equal to 0, there is no value ofbfor which1 minus (absolute value of b) equals 5.

  下面为大家提供一些和这些SAT官方每日一题相似的题目,供大家练习:

graphic

  The scatterplot above shows the number of items purchased at a grocery store by 28 customers and the total cost of each purchase. How many of these 28 customers bought more than 10 items and spent less than $20?

  (A) Four

  (B) Five

  (C) Six

  (D) Seven

  (E) Eight

  The correct answer is A

  Explanation

  Drawing the vertical line "Number of Items = 10" and the horizontal line "Total Cost = "$20" divides the scatterplot into four regions, as shown in the figure below.

graphic

  The lower right region lies below the line "Total Cost = $20" and to the right of the line "Number of Items = 10." Thus the points in this region are exactly the points that represent a purchase of more than 10 items at a total cost of less than $20. (Note that the points on the line "Number of Items = 10" represent a purchase of exactly 10 items, not more than 10 items and, thus, do not meet the given conditions.) There are four points in the lower right region. Therefore, four of the customers bought more than 10 items and spent less than $20.

  以上就是关于2014年1月16日SAT官方每日一题中数学部分的详细内容,包括了题目和选项以及答案,后面附有一道相关的练习题。大家可以在备考SAT的过程中关注SAT每日一题的内容,这样就可以更好有不间断的练习,也就能在日积月累的过程中得到提高。