智能学辅导考试QQ交流群：298985181    

　　智能学辅导中小学QQ交流群：99107564     欢迎关注中小课外辅导官方微博 

1. ABCD is a square of side 3, and E and F are the mid points of sides AB and BC respectively. What is the area of the quadrilateral EBFD ?

　　A. 2.25

　　B. 3

　　C. 4

　　D. 4.5

　　E. 6

Correct Answer: D

Explanation:

(Total area of square - sum of the areas of triangles ADE and DCF) will give the area of the quadrilateral 9 - (2 x ? x 3 x 1.5) = 4.5

2. If n ≠ 0, which of the following must be greater than n?

　　I 2n

　　II n2

　　III 2 – n

　　A. I only

　　B. II only

　　C. I and II only

　　D. II and III only

　　E. None

Correct Answer: E

Explanation:

Remember that n could be positive negative or a fraction. Try out a few cases: In case I, if n is -1, then 2n is less than n. In case II, if n is a fraction such as ? then n2 will be less than n. In case III, if n is 2, then 2-n = 0, which is less than n. Therefore, none of the choices must be greater than n

3. After being dropped a certain ball always bounces back to 2/5 of the height of its previous bounce. After the first bounce it reaches a height of 125 inches. How high (in inches) will it reach after its fourth bounce?

　　A. 20

　　B. 15

　　C. 8

　　D. 5

　　E. 3.2

Correct Answer: C

Explanation:

If after each bounce it reaches 2/5 of the previous height, then after the second bounce it will reach 2/5 x 125. After the third it will reach 2/5 x 2/5 x 125. After the fourth it will reach 2/5 x 2/5 x 2/5 x 125. This cancels down to 2 x 2 x 2 = 8

4. n and p are integers greater than 1, 5n is the square of a number, 75np is the cube of a number. The smallest value for n + p is

　　A. 14

　　B. 18

　　C. 20

　　D. 30

　　E. 50

Correct Answer: A

Explanation:

The smallest value for n such that 5n is a square is 5. 75np can now be written as 75 x 5 x p. This gives prime factors.... 3 x 5 x 5 x 5 x p To make the expression a perfect cube, p will have to have factors 3 x 3 , and hence p =9 n + p = 5 + 9 = 14

延伸阅读：

SAT语法技巧——完全倒装句

SAT语法技巧——部分倒装句

SAT数学选择题解题技巧

更多阅读资料：
/guide/category/40/.html