题目
1. Each week a salesperson receives a commission that is equal to 12 percent of the first $500 of sales plus 20 percent of additional sales. If the salesperson received a commission of $380 last week, what was the total amount of the sales that the salesperson made last week?
A. $1,600
B. $1,660
C. $1,860
D. $2,000
E. $2,100
答案：E
解析：$500*12%=$60; $380-$60=$320; $320/0.2=$1600; $1600+$500=$2100
2. 已知x ≠ 0，
Quantity A: x^2
Quantity B: x(x+5)
A. Quantity A is greater.
B. Quantity B is greater.
C. The two quantities are equal
D. The relationship cannot be determined from the information given.
答案：D
解析：如果x > 0, 则B > A; 如果x < 0, 则B < A，由于x值无法确定，因此两者大小无从比较，所以选D。
3. If x< y, which of the following must be true?
A. 2x< y
B. 2x> y
C. x2< y2
D. 2x-y< y
E. 2x-y< 2xy
答案：D
解析：D项不等式变化可得2x<2y，也就是条件的x
4. The table shows the frequency distribution of the random variable X. What is the median of the distribution of the Value X?
| X | Frequency |
| 0 | 6 |
| 1 | 11 |
| 2 | 18 |
| 3 | 23 |
| 4 | 15 |
B. 1.8
C. 2.0
D. 2.5
E. 3.0
答案：3
解析：题干问X这组数据的中位数。根据右侧的频率可知，总共出现了73个数字，所以中位数应该是第37个数字，所以中位数是3。
5. According to a tax rate formula for a certain year, the amount of tax owed by an individual whose annual income was between $31,850 and $77,100 was equal to a base tax of $4,386 plus 24 percent of the annual income that exceeded $31,850.According to this formula, what was the amount of tax owed by an individual whose annual income that year was $42,000?
答案：6822
解析：题干问，某一年个人收入在$31,850到$77,100之间的税收计算方式为$4,386加上超出$31,850部分的24%。问收入为$42,000的个人这一年需缴纳多少税?
所以我们可以得到所缴税的计算方式=4386+24%*(42000-31850)=6822.