# Math

posted by .

An unfair coin with Pr[H]=0.25 is flipped 95 times. A random variable X is defined as the number of heads that occur. Find the standard deviation.
Any help??

## Respond to this Question

 First Name School Subject Your Answer

## Similar Questions

1. ### Math

*Sigh* Can someone explain to me how I would work through this problem?
2. ### probability

Suppose an unfair coin comes up heads 52.2% of the time if it is flipped. If the coin is flipped 26 times, what is the probability that: a) it comes up tails exactly 12 times?
3. ### math

a fair coin is flipped 5 times the random variable is x is defined to be the number of heads that are observed identify the probability mass function of the random variable x. x P(x)
4. ### Finite

Assume that the coin is weighted so that Pr[H] = [ 1/11], and that it is flipped 9 times. The random variable X is defined as the number of heads in the 9 flips. What is E[X]?
5. ### statistics

air coin is flipped 20 times. a. Determine the probability that the coin comes up tails exactly 15 times. b. Find the probability that the coin comes up tails at least 15 times. c. Find the mean and standard deviation for the random …
6. ### Math

A coin is loaded in such way that a tail is three times as likely to occur as a head. If the coin is flipped twice. Find the probability that two heads occur
7. ### Math

A coin is loaded in such way that a tail is three times as likely to occur as a head. If the coin is flipped twice. Find the probability that two heads occur
8. ### Math

A coin is loaded in such way that a tail is three times as likely to occur as a head. If the coin is flipped twice. Find the probability that two heads occur
9. ### probability

A fair coin is flipped independently until the first Heads is observed. Let K be the number of Tails observed before the first Heads (note that K is a random variable). For k=0,1,2,…,K, let Xk be a continuous random variable that …
10. ### Math (statistics)

The probability of obtaining heads on a biased coin is 0.4. The coin is tossed 600 times. a. i. Write down the mean number of heads (240) ii. Find the standard deviation of the number of heads (12) b. Find the probability that the …

More Similar Questions