4立方体体积是8,那一个面的面积当然是4咯
5. Ms.Smith got an 8 percent cost-of-living raise of $20 per week
Ms.Smith's new weekly salary $260
5 x*0.08=20,那x+20=270>260
6. On a certain number live, if -7 is a distance of 4 from n and 7 is a distance of 18
from n then n=
A.25 B.11 C.3 D.-3 E-11
6应该是-11
7. For all real numbers a and b. if a·b=a(a+b), then a·(a·b)=
A. a2+ab B a2+ab+a C a2+a+b D a3+a2b E a3+a2b+a2
注:a2表示a平方,a3表示a立方
7新定义的运算a·b=a(a+b), 那a·(a·b)=a·(aa+ab)=a(a+aa+ab)=aa+aaa+aab
8.secretary typed 6 letters,each of which had either 1 or 2 pages.If the secretary typed 10 pages in all, how many of the letters had 2 pages?
A 1 B 2 C 3 D 4 E 5
答案是D,题目我都看不懂,是啥意思呢?
这是说秘书打六封信,没一封信要1页或者两页。如果秘书总共打了10页,那么有多少封信是两页?
解答:设有x封,则2x+(6-x)=10,解得x=4.
9 how many of the five numbers above are each equal to the product of an integer and an odd integer that GREater than 1?