A committee has to choose four out of ten companies (C1 and C2 included) for the annual award. What is the probability that C1 and C2 are both selected?
Give your answer as a fraction.

What is the probability that A and B are both selected when you select 40 people out of a group of 100 (A and B included)?
Give your answer as a fraction.

Several 0 and 1 are arrange in a 10*10 palace as follows. Among all the number 0, what is the probability that they are arranged in both an odd row and an odd column?
Give your answer as a fraction.

In a bag, only red and blue balls (at least 2 balls for each color) are included.
Quantity A: The probability that red ball is selected when you add a blue ball from the box
Quantity B: The probability that red ball is selected when you remove a red ball from the box

What is the probability that the one 3digit and one 2digit integers that could be formed out of 1, 2, 3, 4 and 5 (each figure is used for only once) are both even integers?
Give your answer as a fraction.

Mark flips 2 dimes (10 cents each) and 1 nickel (5 cents) together for twice. What is the probability that the total value of coins on the heads is 15 cents?
Give your answer as a fraction.

Mark flips 2 dimes (10 cents each) and 1 nickel (5 cents) together. What is the probability that the total value of coins on the heads is 15 cents?
Give your answer as a fraction.

When selecting two numbers without replacement from 5, 8, 9, 9, 9, what is the probability that the sum of the two selected numbers is a multiple of 3?
Give your answer as a fraction.

Eight points are equally spaced on a circle. If 4 of the 8 points are to be chosen at random, what is the probability that a quadrilateral having the 4 points chosen as vertices will be a square?

If points A and B are randomly placed on the circumference of a circle with radius 2, what is the probability that the length of chord AB is greater than 2?

p is the probability that event E will occur, and s is the probability that event E will not occur.
Quantity A: p+s
Quantity B: ps

Among Event A, Event B and Event C, Event B and Event C are mutually exclusive
0 < P(A) < 1, P(A)=2P(B)=3P(C)
Quantity A: 2/3 P(A)
Quantity B: P(B or C)

In a box of 5 red socks, 4 blue socks and 3 yellow socks, someone selects a sock first, puts it back and then selects another sock. What is the probability that he or she selects yellow socks for both time?
Give your answer as a fraction.

In box H, there are 5 red balls, 3 green balls and 2 yellow balls, while In box R, there are 3 red balls and 7 yellow balls. If someone selects one ball from each box, what is the probability that he or she selects at least one yellow ball?

What is the probability that the selected number are the same when selecting one letter from each of the word JOHNONS and JONES?
Give your answer as a fraction.

Set A: {71,73,79,83,87}
Set B: {57,59,61,67}
If one number is selected at random from set A, and one number is selected at random from set B, what is the probability that both numbers are prime?

20 boys and 40 girls are in Group A, while at least 7 boys, together with some girls are in Group B. To choose one person from each of the group, the probability that both are boys is no greater than 1/15. Which of the following statements must be true?
Indicate all such statements.

A and B are independent events, and the probability that both events occur is 1/2. Which of the following could be the probability that event A occurs?
Indicate all such probabilities.

Events A and B are independent.
The probability that events A and B both occur is 0.6
Quantity A: The probability that event A occurs
Quantity B: 0.3

A box contains 10 balls numbered from 1 to 10 inclusive. If Ann removes a ball at random and replaces it, and then Jane removes a ball at random, what is the probability that both women removed the same ball?
