2. 一条绳子长一米,分成长短两端,the ratio of the longer segment to the shorter segment is 2/3 the ration of the origional length to the longer segment. IF X represents the length of the longer segment 然后用X表达出这个式子就可以。 (答案是一个一元二次方程)
3. 正整数n, if n is divided by 10, whether the remainder R is 5?
条件1:n的平方除以5的余数是0
条件2:n的平方除以4的余数是1 我选了C
6.K is 1 more than the product of all the prime numbers between 2 and 29, inclusive. 给出几个式子判断哪几个对
I. K has a prime factor that is larger than29
II. K can be divided by the prime numbers between 2 and 29
III. K。。。。失忆了。 只有这个是对的。
7. Pump A 的效率 is 5 times more than of Pump B. A、B一起完成一个工作要10个小时。求A单独完成这个工作的时间。(12hour 这题more than 5倍就是A=5B 不知道题目为什么要more than 这样的表达。 只有当5倍算的时候有答案)
8. IS n an even? (B)
条件1:n(n+1)/2是even
条件2:n(n+2) 是even