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Probability
The probability of a certain event is a number expressing the likelihood that a specific event will occur, expressed as the ratio of the number of actual occurrences to the number of possible occurrences. In mathematics, it is a measure of how often an event will happen and is the basis of statistics.
14,643 Questions
What is probability of each suit in a deck of cards?
The probability of each suit in a standard deck of cards is 13 in 52, or 1 in 4, or 0.25.
What is the probability of a woman having four boys?
-- Zero if she has 0, 1, 2, or 3 children.
-- Roughly 1/16 = 6.25 percent if she has 4 children.
-- Roughly 5/32 = 15.6 percent if she has 5 children.
-- Roughly 15/64 = 23.4 percent if she has 6 children.
What is the probability of rolling a sum less than 6 with two dice?
There are 36 permutations of two dice. Of these, 10 sum to less than six; 1+1, 1+2, 1+3, 1+4, 2+1, 2+2, 2+3, 3+1, 3+2, and 4+1. The probability, then, of rolling a sum less than six is 10 in 36, or 5 in 18, or about 0.2778.
What are the probability of having a male baby in the womb?
Approx 1/2, except that while it is in the womb, it is not a baby!
What is the probability of guess a two digit number?
On a number line, the digits from 10 to 99 are all two digit numbers. How many numeber are that? There is a short cut. You can subtract 10 from 99 and that gives you the number of numbers between 10 and 99 including 10, but you need to add one more to include 99 as well. So, 10 from 99 is 89 adding 1 is 90 ,which is the amount of numbers total that are two digit. The probability of guessing a two digit number is 1/90 =D
There is not enough information about the the distribution of the number of people known by each individual - nor the averages. It is therefore no possible to give an answer any more precise than "the probability will be infinitesimally small".
What is probability of throwing 9 heads in a row?
If you toss a coin often enough the probability is 1.
The probability of 9 H in the first 9 tosses is (1/2)9 = 1/512
How do you reduce the terms if the probability of drawing a face card is 12 in 52?
You reduce the terms the same way you reduce an ordinary fraction, by finding the greatest common divisor and dividing both numbers by that divisor. In this case, the greatest common divisor is 4, so you divide by 12 and 52 by 4, giving you 3 and 13, so if the probability of drawing a face card is 12 in 52, it is also 3 in 13.
What is the purpose of doing the z-score?
The Normal distribution is frequntly encountered in real life. Often a matter of interest is how likely it is that the random variable (RV) being studied takes a value that it did or one that is more extreme. This requires a comparison of the observed value of the RV with its Normal distribution. Unfortunately, the general Normal distribution is extremely difficult to calculate.
The Normal distribution is defined by two parameters: the mean and the variance (or standard deviation). It is impossible to tabulate the distribution of every possible combination of two parameters - both of which are continuous real numbers. However, using Z score reduces the problem to that of tabulating only one the Normal distribution: the N(0, 1) or standard Normal distribution. This allows the analysis of an RV with any Normal distribution.
When you roll four dice how many different number combinations could you roll that will total 14?
There are 8 different combinations.
There are 145 permutations that total 14.
Not asked, but answered for completeness sake; there are 1296 possible permutations of four dice, making the probability of a sum of 14 being 145 in 1296 or about 0.1119.
What is the probability that two cards in a 52 card deck are the same color?
In a standard deck the probability is 0. There are not two, but 26 cards of the same colour.
The number of permutations of the letters MASS where S needs to be the first letter is the same as the number of permutations of the letters MAS, which is 3 factorial, or 6. SMAS SMSA SAMS SASM SSMA SSAM
How do you know if a z score is positive or negative?
A negative Z-Score corresponds to a negative standard deviation, i.e. an observation that is less than the mean, when the standard deviation is normalized so that the standard deviation is zero when the mean is zero.
What is the probability of spinning a 2 on a 1-6 spinner if I spin it 60 times?
The probability of getting a 2 is 1 - (1/6)60 = 1 - 2.05*10-47
What is the probability that a spade or a jack is drawn out of 52 cards?
The probability of drawing a jack is 4 in 52. The probability of drawing a spade is 13 in 52. The probability of drawing a jack or a spade is 4 + 13 - 1 in 52, with the -1 compensating for one of the jacks also being a spade. 4 + 13 - 1 in 52 is 16 in 52, which is also 4 in 13, or about 0.3077.
What is the probability of getting either a six or a one from a single roll of a die?
2 in 6, or 1 in 3, or about 0.3333.
How many permutations of the letters in the word Louisiana are there?
The number of permutations of the letters in the word LOUISIANA is 9 factorial or 362,880. However, since the letters I and A are each repeated once, you need to divide that by 4 to determine the number of distinct permutations, giving you 90,720.
What are the expectations for the following 1 bets on a US roulette wheel?
there are 38 slots on a US roulette wheel, (1-36, 0 and 00)
but they only payout 35 times your stake.
european tables have 37 slots but the same edge, if you do the maths american casinos have almost double the edge of european tables. like they need it...bit of a liberty if you ask me.
Getting heads is just as likely as getting tails.
So the expected number of each is even.
There are no other possibilities so you should expect 5 of each.
Naturally, if you actually flip a coin 10 times, it may come out 6/4, 4/6, 7/3 or even 10/0, but 5/5 is the most likely outcome.
