越來越多的朋友加入到GMAT的考試大軍中，準備邁向牛逼哄哄的商學(xué)院去，數(shù)學(xué)是GMAT考試中容易拿下的部分，但是GMAT數(shù)學(xué)我們知道對基礎(chǔ)知識的要求是比較高的。我們在做題的時候常常會碰到很多概念。下面就是出國留學(xué)網(wǎng)為大家?guī)淼摹?font color="#ff0000">gmat數(shù)學(xué)備考常見概念》，記得背好，希望對大家都有所幫助。
下面我們主要列出GMAT數(shù)學(xué)概念中描述統(tǒng)計(descriptive statistics)部分詞匯：
1.平均數(shù)(average or arithmetic mean)
2.中數(shù)(median)
To calculate the median of n numbers，first order the numbers from least to greatest;if n is odd，the median is defined as the middle number，while if n is even，the median is defined as the average of the two middle numbers. For the data 6, 4, 7, 10, 4, the numbers, in order, are 4, 4, 6, 7, 10, and the median is 6, the middle number. For the numbers 4, 6, 6, 8, 9, 12, the median is (6+8 )/2 = 7. Note that the mean of these numbers is 7.5.
3.眾數(shù)(mode)：一組數(shù)中的眾數(shù)是指出現(xiàn)頻率最高的數(shù)。
例：the mode of 7，9，6，7，2，1 is 7。
4.值域(range)：表明數(shù)的分布的量，其被定義為最大值減最小值的差。
例：the range of–1，7，27，27，36 is 36-(-1)= 37。
5.標(biāo)準方差(standard deviation)：
One of the most common measures of dispersion is the standard deviation. Generally speaking, the greater the data are spread away from the mean, the greater the standard deviation. The standard deviation of n numbers can be calculated as follows:
(1)find the arithmetic mean ;
(2)find the differences between the mean and each of the n numbers ;
(3)square each of the differences ;
(4)find the average of the squared differences ;
(5)take the nonnegative square root of this average.
Notice that the standard deviation depends on every data value, although it depends most on values that are farthest from the mean. This is why a distribution with data grouped closely around the mean will have a smaller standard deviation than data spread far from the mean.
溫馨小提示：整理的GMAT考試數(shù)學(xué)部分常見的幾個概念，GMAT數(shù)學(xué)對于考生的基礎(chǔ)知識要求是比較高的。所以考生們在復(fù)習(xí)的時候要多多注意，GMAT入門的考生復(fù)習(xí)數(shù)學(xué)先從背誦基礎(chǔ)知識開始做起吧。