2。a, b 都是 3 位数,和是 4 位数,a>b, the tenth of a is 7, the tenth of b is 5, which one is correct?
I.
II. the tenth of the sum is 2
III. the hundredth of b is at least 5.
答案是III (不一定吧?)
3。some balls in a box, 9 blue, some red, randomly take 2 blue balls out of the box, the probability is 6/11, how many balls in the box. (66)
4。Two points in the coordinate, B (1,2), C (4,3), ask for the coordinate of A
1) AC=3 2) AB=2 ( the numbers are not accurate)
答案是D
5。40 students eat corn, pea, squash, 21 students like only one of them, 3 only like corn and pea, ask the maximum of like three of them?(16)