1、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?
我觉得这道题x的最大值为6,最小值为0,所以选6.
a.5 b.6 c.10 d.12 e.36
选D，最大为6，最小为-6.
2、三角形ABC，角B=X度，X>90 度，比较三角形的周长与3倍AC的长度的大小，答案是B
AC是最大边,所以AB+BC+AC
2.0
比较the greatest value of p(1-p)与1/2的大小，答案是C
答案错了,选B p+(1-p)>=2p(1-p)^1/2 => p(1-p)<=1/4 < 1/2
3、for the line with equation y=ax+b,the x-intercept os twice the y-intercept
比较the slope of the line 与1/2的大小，答案是D，但算出来是-1/2呀
还有截距为零的情况,所以D.
4、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%,题目没看懂
意思是一个货币市场上个月共结余48000，用它赚了360的利息，问以年单利计算每年利率是多少?
360*12/48000=9%
5、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
首先这道题我是对multilples of ....不大明白,这是什么意思啊?其次这道题怎么解呢?
在小于360的30的公倍数中,也是12的公倍数的占多少?30N≤360, 得N≤12,所以共有12个数满足题干.
又12与30的最小公倍数为60,其实此题是求是60的倍数又小于等于360所占比例,同理求出为6
所以,6/12=答案E