问题
解答题
| 将1、2、3三个数字随机生成的点的坐标，列成下表，如果每个点出现的可能性相等，那么从中任意取一点，那么这个点在函数y=x图象上的概率是多少？ | |||||||||
|
答案
解：∵从1、2、3三个数字中随机生成的点有9个，且每个点出现的可能性相等，其中在函数y=x图象上的点有（1，1）、（2，2）和（3，3）共3个，
∴点在函数y=x图象上的概率是
。
搜题请搜索小程序“爱下问搜题”
| 将1、2、3三个数字随机生成的点的坐标，列成下表，如果每个点出现的可能性相等，那么从中任意取一点，那么这个点在函数y=x图象上的概率是多少？ | |||||||||
|
解：∵从1、2、3三个数字中随机生成的点有9个，且每个点出现的可能性相等，其中在函数y=x图象上的点有（1，1）、（2，2）和（3，3）共3个，
∴点在函数y=x图象上的概率是。
| 阅读理解。 | ||||
| Jack is a high school student. He is seventeen years old. He is in Grade two now. He had a bad stomachache three days ago. He went to see the doctor. The doctor gave him a bottle of medicine. Here are the words on the bottle: Stomachache medicine You must shake (摇晃) the bottle before you take it. You must take it three times a day. You should take it after meals.
place. Take it before Oct.31, 2009. | ||||
| 1. Jack should take the medicine ______. | ||||
[ ] | ||||
| A. before meals B. after meals C. before sleep D. after sleep | ||||
| 2. Jack should take ______ of the medicine a day. | ||||
[ ] |
| A. 1 teaspoon B. 4 teaspoons C. 9 teaspoons D. 2 teaspoons |
| 3. Jack should ______ before taking the medicine. |
[ ] |
| A. eat no food B. drink no milk C. shake the bottle D. drink some water |
| 4. Children can take the medicine when they're ______ years old. |
[ ] |
| A. under 4 B. more than 4 C. more than 16 D. between 8and 15 |
| 5. Jack ______ the medicine after October 31,2009. |
[ ] |
| A. has to take B. has to sold C. can take D. can't take |