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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
If the probability of an event will occur is p, then the probability that it will occur in n trials is pn.(That's p raised to the n power). So if you bet on 12 numbers, then (38-12=26) numbers are empty. The probability of the ball landing on one of these empty numbers is 26/38. So (26/38)^11 = 0.01538, which is about 1.538 % or a 1 in 65 chance.
When a quarter is tossed four times How many times are exactly three tails tossed?
Out of the 16 possible outcomes for a coin tossed four times, 4 of them result in 3 Tails & 1 Head. They are: TTTH, TTHT, THTT, and HTTT.
What is the probability of rolling a number that is divisible by 3 or a 5?
If you roll the die often enough the probability is near enough 1 so as to make no difference.
On a single roll, the probability is 1/2.
How many 4 digit numbers can you make that contain 5?
There is a clever but tricky way to solve this. If we have to find the number of 4-digit integers that contains at least one 5, we can also find the number of all the 4-digit integers and the number of integers that do not contain any 5's and subtract it from the first number. This is called complementary counting.
So, first of all, we must find the number of 4-digit numbers there are. There are 9000 of them.
Now, we find the number of 4-digit integers without 5's. By thinking a little bit, we see the first digit must be from 0~9 excluding 5. That is a total of 9 numbers. This is the same for the next three digits. Therefore, there are 94 = 6561 4-digit numbers without a 5.
Finally, we can subtract. 9000 - 6561 = 2439
Why is the normal probability distribution widely used in practice?
Suppose you have a random variable, X, with any distribution. Suppose you take a sample of n independent observations, X1, X2, ... Xn and calculate their mean. Repeat this process several times. Then as the sample size increases and the number of repeats increases, the distribution of the means tends towards a normal distribution. This is due to the Central Limit Theorem.
One consequence is that many common statistical measures have an approximately normal distribution.
What events have a .3 perent probability?
Selecting an integer at random that ends in 1, 4 or 6 (or any of the 120 sets of three 1-digit values).
Picking a black ball out of a bag when there are 3x black balls and 7k balls of other colours.
When rolling a dice what is your chance of getting three?
1 in 6. As there are 6 different numbers. 1/6 as a fraction
What is the probability of rolling an odd number on a 20 sided dice?
Assuming the sides are labelled one to twenty and that all sides are the same shsp and size and that the dice in not biased in any way, then there will be a 50% chance of getting an odd number.
What is the ratio of 4 blue marbles to 6 white marbles?
The ratio of 4 blue marbles to 6 white marbles can be said as 4:6, 4 to 6, or 4/6.
This can then be simplified to 2:3 by a factor of 2.
(4/52)*(3/51)*(2/50) = 24/132600 = 0.000181
What is a run of five cards of different suits?
A run of 5 cards, all sequential ( Ace, 2, 3, 4, 5, different suits) for example, in poker is known as a straight.
If these sequential runs of cards are of the same suit, then they are known as a straight flush.
It is 13.2%
What is the probability of 1 6 4 on 3 rolls of a die?
What is the probability of 1, 6, 4, on 3 rolls of a die
Why is an increase in the number of varieties of a good regarded as a gain from trade?
More varieties provide buyers with more options. More options allow buyers to better match their needs and costs, thus achieve more value for their money.
"Dice" is both singular and plural. Usually, it's one "die" and two "dice."
The probability of getting a red chip on the first draw is 5/15.
The probability of getting a red chip on the second draw, given that the first draw
gave a red chip that was not replaced in the bag is 4/14.
The probability that the first and second draw give a red chip is ;
5/15 x 4/14 = 2/21 ≈ 0.0952 = 9.52 %
If there were just 7 green and 4 blue involved you would need to pick out at least 8, since this would cover picking out all the greens plus 1 blue. Any choice of less than 8 might produce only greens.
Now in the case where we have 7 green, 4 blue and 5 red marbles we would need to choose 7 + 5 + 1 = 13, since any number less than 13 could be covered by selecting (by chance) all the 7 greens and all the 5 reds with no blue at all.
In this case the answer is found by totalling all numbers other than the smallest, and then adding 1.
When tossing 5 coins simultaneously what is the probability that at least 1 head is showing?
Probability of no heads = (0.5)^5 = 0.03125
Probability of at least one head = 1 - probability of no heads = 1 - 0.03125 = 0.96875
Two six sided dice are rolled which number has the lowest probability of being rolled?
If two six sided fair dice are rolled, the sum of the result of both dice that has the
lowest probability to come up is 2 and 12. P(2) = 1/36. P(12) = 1/36.
How many ways can 5 friend sit together at the movies in 5 seats?
120 ways if ABCDE is considered different from EDCBA. In these two cases, the same people are next to one another , only the left and right re changed.
