北美JJ, 9/22, 一战770 http://bbs.topway.org/dispbbs.asp?boardid=64&id=167132&star=1#470507 Math 451. 说(x2-5x-1)2-25能写成(x-a)(x-b)(x-c)(x-d),问abcd等于多少?
452. 三角形ABC,有一条边是2,AB等于BC,有一个角是60°,问周长
453. 0<x<1,x为小数,is tenth digit of x nonzero? A 16x是整数
B 8x是整数
454. 求4+5/a最接近的整数(nearest rounded to) A a>10 B 0<a<20 455. 说一帮学生选课,选历史地理政治的分别是A,B,C个人(ABC 都是具体数字),问选其中2科的是多少人?
I.
三科都选的是D人(具体数)
II.总共52个人参加了选课
456.People who earn more than 40000 for their salaries should submit 6% of 40000 and x% for the part exceeding 40000. If a people earn50000 and submit 2600, what is X? 457.x和y在数轴上,x在原点的左边,问x和y之间的距离
A..4是x和y的halfway B.0是x和y/2的halfway 458. 三个班ABC,有9个人同时上A和B,14个人同时上A和C,没人同时上B和C,问有几个学生至少上一个班?
条件一:三个班人数相等
条件二:三个班各自的人数相加为325 459. f(a)=10a^2, what is the value of f(a)f(b) A. f(a)=10 B. f(a)f(b)=f(ab) I chose B 460 . 一个数等于2的51次方,另一个数等于2的x次方乘以3的立方,二者有相同个数的正整数因子,问x等于多少
461. x y z的标准偏差是a,问下面哪一些标准偏差也是a?
1、x+1 y+1 z+1 2、2x 2y 2z 3、x平方 y平方 z平方
462.一条线y=x+a在直角坐标系内,同时与x和y轴相交,构成一个三角形,面积大于1,问下列哪些a的取值范围可以保证上述条件
463. 设f(x,y)=x的阶乘/(x-y)的阶乘;那么满足f(6,y)>20的y的最小值是多少
464.(360^2)^3=? I chose 2^18x3^12x5^6 465. 一个鞋子店,第一双是FULL PRICE,第二双可以50%OFF,PROVIDED IS LESS THAN THE FIRST PAIR(这里开始迷茫)。然后又说第二双鞋子的全价比第一双的全价少35%,,最后问你两个一起买的DISCOUNT。
20% 466. 2 to 40 inclusive the sum of consecutive even number is 420 1 to 39 inclusive the sum of consecutive odd number? 467. 买票,大人6块,小孩3块,问卖票的能否卖到2500 1) the number of children 2) 卖了850张
B 468. 7个人,岁数分别是22,24,28,32,33,37,X。问X是多少?
1) range是17 2) median是1. 469. n=km+b,n<0,m>0,b>0怎么怎么的,说b叫余数,然后问-100的余数是多少
470. . 20. t<t^3<t^2 what is the possible value of t I chose -1/2 471. A circle, center at (0,0), radius 50. P(50,0), Q is on the circle(didn't shown in the picture), What is PQ? A. Q, x coordinate(-40) B. Q. y coordinate (-30) 472. 2y=5 1. slope is 0 2. parallel to X axis 3. parallel to Y axis 473. Y country has 6o million people. It has 6 district, K,L,M,N,O,P, each district's population is greater than or at least equal to the next district. N has 21% of the total population, P has 2 million, what is the greatest number of population of O 474. D点和E点分别为中点
半径为r 求阴影部分面积
面积等于一个四分之一减掉等腰直角三角形
记得乘以二
因为是两个半圆
答案r^2(pai-1)/2 475. (1,2) is on the y=ax^2+bx+c, is (-1,2) also on it? A. f(a)=f(-a) for all f(x)=ax^2+bx+c B. b=0 476. k@ = k+1 if k is odd, k-1 if k is even. Is (a@)^2x(b@) even? A. a is even B. b is odd 477.要求 5X-3Y=? A.(x/0.3)-(Y/0.5)=0.1 B.(x/0.5)-(Y/0.3)=0.1 478. |x-5|<2 ,which one couldn't be x x=-7 479. car 50 mile per hour, 30 mile per gallon, 12 gallon tank, 5 hours, what is the percentage of gas left in tank? math 51 |