There 20 people competing in a contest. If first place earns $100, second place earns $50 and third place earns $25, how many ways can the three winners be selected?

There 20 people competing in a contest. If first place earns $100, second place earns $50 and third place earns $25, how many ways can the three winners be selected?

I need to find the theoretical prob. of each sum of two 20 sided die and 3 six sided die. Is there a formula for this, because I can't find any. PLEASE HELP

There are four cards that are yellow, blue, green and purple.

assume that when adults with smartphones are randomly selected, 45% of them use them in meetings or classes. If 8 adult smartphone users are randomly selected, find the probability that at least 3...

Assume that when adults with smartphones are randomly selected, 42% use them in meetings or classes. If 10 adult smartphone users are randomly selected, find the probability that at least 77 of them...

An experiment consists of tossing a regular die with faces numbered 1 through 6. Use the following events to determine the probabilities in the following: E: Obtaining an even number F:...

The dice game called craps has the following rules: If the player rolling the dice gets a sum of 7 or 11, he or she wins. If the player rolls a sum of 2, 3, or 12, she or he loses. If the first...

Suppose there are 5 red marbles, 10 purple marbles and 20 blue marbles in a jar. What is the probability of choosing a purple marble and then a purple marble if the first marble is not replaced?...

Suppose there are 5 red marbles, 10 purple marbles and 20 blue marbles in a jar. What is the probability of choosing a purple marble and then a purple marble if the first marble is replaced?

A fair six-sided die is rolled until it comes up 6. What is the probability that the number of rolls will be exactly 5 given that it takes at least 2 rolls?

Combination or permutation

How many outcomes are possible if a dice is rolled five times?

When the health department tested private wells in a county for two impurities commonly found in drinking water, it found that 20% of the wells had neither impurity, 40% had impurity A, and 50% had...

A document is signed with an ElGamal signature. The probability that a signature is forged is (.1). Find the probability that at least one of the three Rob’s signatures is forged.

Usually, errors are found in 10% of lines of code written by software engineers at Error Free Code, Inc. What is the probability that in a randomly selected sample of 5 lines of code none of them...

There are 4 red candies and 6 blue ones in a box. If a child randomly takes 3 candies one by one, find the probability that the first is red and the last two are blue. NEED HELP ASAP...

biology

A manufacturer knows that 12 percent of its 200 computer monitors are defective. If 3 monitors are randomly selected, how do I find the probability of the following outcomes? P(1st monitor...

A personnel director has two lists of applicants for jobs. List 1 contains the names of five women and two men, whereas list 2 contains the names of two women and six men. A name is randomly...

Suppose Pr(A) = 0.58, Pr(B) = 0.45 and B ⊆ A. Find: a) Pr(A∩B) b) Pr(A∪B)