In a probability experiment, G and H are independent events. The probability that G will occur is r, and the probability that H will occur is s, where both r and s are greater than 0.
Quantity A: The probability that either G will occur or H will occur, but not both
Quantity B: r+sr*s

The probability that one can get through on any of the n telephone lines is 0.7 (each telephone line is separate). At least how many telephone lines do you need to ensure that the probability you can get through reach over 0.99?

What is the probability of selecting different colors when selecting 2 balls out of a box of 10 red balls and 6 blue balls without replacement?
Give your answer as a fraction.

In a box of 10 balls, 4 are red while 6 are blue. What is the probability that all the 3 balls are red when randomly selecting 3 balls out of the box without replacement?
Give your answer as a fraction.

There are only similar number of red and green balls in a box. A person first randomly selects a ball from the box without replacement, and continues to select another ball. Which of the following probability is 1/2?
Indicate all that are true.

The probability that a component fails during first use is 0.1. If the component doesn`t fail during first use, then the probability that the component won`t fail in the following six months is 0.8
Quantity A: The probability that the component won`t fail within six months
Quantity B: 0.75

Among 5 different red envelopes, 2 include cash, 3 include gifts. If you choose two red envelopes without replacement, what is the probability that cash is selected at least once?
Give your answer as a fraction.

In a box, the probability that the red ball is selected is 5/8. Mark randomly selects balls twice from the box without replacement. If he didn`t get a red ball in the first attempt, then the probability that he gets a red ball in the second attempt is 2/3. What is the probability that Mark get at least one red ball?
Give your answer as a fraction.

In a box, the probability that the red ball is selected is 5/8. Mark randomly selects balls twice from the box without replacement. If he didn`t get a red ball in the first attempt, then the probability that he gets a red ball in the second attempt is 2/3. What is the probability that Mark gets one red ball either in the first attempt, or in the second attempt, but not both?
Give your answer as a fraction.

In seven continuous tosses, Event X or Event Y appears randomly each time. If Event X appear first, then Event X appears the next time is 0.3. If Event Y appears first, then Event Y appears the next time is 0.4. If Event X appears in the fifth time, then what is the probability that Event X appears in the seventh time?
Give your answer as a fraction.

For a certain probability experiment, the probability that event A will occur is 1/2 and the probability that event B will occur is 1/3. Which of the following values could be the probability that the event A∪B (that is, the event A or B, or both) will occur?
Indicate all such values.

The probability that Event A occurs is 0.63, while the probability that Event B occurs is 0.58. What is the greatest probability that Event A and B both occurs?
Give your answer as a decimal.

The probability that Event A occurs is 0.45. What is the greatest possibility that Event A and Event B both occurs?
Give your answer as a decimal.

The probability that Event A occurs is 0.7, The probability that Event B occurs is 0.4. Which of the following could be the probability that Event A and B both occurs?
Indicate all such probabilities.

The probability that Event A occurs is 0.5, while the probability that Event B occurs is 0.3. What is the maximum possibility that both events do not occur?

If 125w + 25x + 5y + z = 264, and w, x, y and z are integers no less than 0 and no greater than 5, then the sum of w, x, y and z could be?
Indicate all such values
