GRE考試易錯數學題詳解

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GRE數學對中國學生來說是比較好拿分的部分。同學們在GRE考試中都力求拿到滿分。下面是小編為大家整理收集的關於GRE考試易錯數學題的相關詳解,希望對大家有所幫助。

GRE考試易錯數學題詳解

1 the sum of two numbers, x and y, equals twice their products. if x=3, what is the value of y?

這道題沒大看懂?請問大家是這樣麼?x+y=2(x+y)

x+y=2xy,求y.

2 if x is an integer and x2(x的平方)<37,what is the greatest possible value of x minus the least possible value of x?

我覺得這道題x的最大值為6,最小值為0,所以選6.

a.5 b.6 c.10 d.12 e.36

選D,最大為6,最小為-6.

3 三角形ABC,角B=X度,X>90 度,比較三角形的周長與3倍AC的長度的大小,答案是B

AC是最大邊,所以AB+BC+AC

2.0

比較the greatest value of p(1-p)與1/2的大小,答案是C

答案錯了,選B p+(1-p)>=2p(1-p)^1/2 => p(1-p)<=1/4 <1/2

4 for the line with equation y=ax+b,the x-intercept os twice the y-intercept

比較the slope of the line 與1/2的大小,答案是D,但算出來是-1/2呀

還有截距為零的情況,所以D.

5 a certain moneymarket account that had a balance of $48000 during all of last monthearned $360 in interest for the month. at what simple annual interestrate did the account earn interest last month?

答案是9%,題目沒看懂

意思是一個貨幣市場上個月共結餘48000,用它賺了360的利息,問以年單利計算每年利率是多少?

360*12/48000=9%

6 Of the positive integers that are multiples of 30 and are less than or equal to 360,what fraction are multiples of 12?

a.1/6 b.1/5 c.1/3 d.2/5 e.1/2

首先這道題我是對multilples of ....不大明白,這是什麼意思啊?其次這道題怎麼解呢?

在小於360的30的公倍數中,也是12的公倍數的佔多少?30N≤360, 得N≤12,所以共有12個數滿足題幹.

又12與30的最小公倍數為60,其實此題是求是60的倍數又小於等於360所佔比例,同理求出為6

所以,6/12=答案E

7 A certain teacher has a total ofat least 110 students enrolled in her the teachers has anaverage (arithmetic mean) of exactly 27 students enrolled per is the least possible number of classes that the teacher couldhave?

a.3 b.4 c.5 d.6 e.7

我覺得這道題就是用110除以27就好了,可是答案是選c的

是呀,110/27=4.04,如果是4個班,那麼總人數為108,還剩2個。當然是5個班了。

8 a delivery service charges $0.02 per ounce for the first 16 ounces ofa shipment and $0.15 for each additional ounce of theshipment,(1pound=16ounce)

the delivery charges for x shipments weighing a combimed total of the pounds vs 567.00

這道題答案選的是D,不明白怎麼會無法確定呢?我是這樣算的:16×0.2+(25*16-16)×0.15...這樣對麼?

因為x是個未知數,所以你無法確定它的值。