#### 题目列表

How many different 5-digit numbers can be formed by one "1",two "2",and two "5"?
Someone rearranges all the letters from the word "Mississippi"

#### Quantity A

The probability that all the same vowel letters are arranged together

#### Quantity B

The probability that all the same consonant letters are arranged together

There are 20 students in class with 10 girls and 10 boys. A teacher randomly selects some students and the first 6 students are all girls.

#### Quantity A

The probability that the 7th student is a girl

#### Quantity B

$\frac{2}{7}$

The room number is between 200 and 999, inclusive. If the double room has the unit digit of 3,whats the ratio of the number of double room to all the room?
When randomly selecting 2 balls out of a box of 6 red balls and 10 blue balls, what is the probability that 1 red ball and 1 blue ball are selected at the same time? fraction.
Select two numbers simultaneously from 1, 2, 3, 4, 5, what is the probability that the product of two numbers is odd?
4 out of 10 people are majored in mathematics. If you want to choose a team of 3 people out of these 10 people, what is the probability that there are at least 2 mathematics professionals in this team?
From Room Number 100 -799, inclusive, the units digit of a double room is 5 or 6, the tens digit of a double-room is 6 or 7, when a room is randomly selected, whats the probability that it is a double room?
There are 5 points on a number line, and two are on the left of 0, three are on the right of 0. If three numbers are chosen from those 5 points, what is the probability that all of them are positive integers?
Two numbers are to be selected at random and without replacement from the set {1,3,5,7,9,11}. What is the probability that the product of the two selected numbers will be greater than 50?
If Event X happens, it has five possible outcomes (A, B, C, D and E) in total. The probability that outcome A, B and D respectively occurs is listed as follows. If the probability that outcome C occurs is twice the probability that outcome E occurs, then what is the probability that outcome C occurs?

When X and Y competes with each other (no ties), the probability that X wins is twice the probability that Y wins. What is the probability that Y wins for three consecutive times?
The probability that event A occurs is p, and the probability that event A does not occurs is q. If p-q=0.2,what is the value of p?
Consider two cubes with faces numbered 1 to 6 each, what is the probability that the first roll will be an odd number and the second roll will be a 5?
A fair coin is tossed several times. If the coin is getting a head for the first time. what is the probability of getting three heads on consecutive three tosses?
There are 400 boys and 600 girls, 20% of boys and 23% of girls chose rock music. Now choose one boy and one girl, what is the probability that both of them like rock music?
_____%
There are ten a and eight b, randomly select two letters without replacement, then what is the probability that the first letter is a and the second is b?
____%
Event A and event B are independent event. If the probability that event A occurs is 0.85 and the probability that event B occurs is 0.4,what is the probability that only event A occurs?