What have you tried?mattamimi said:1)the probability of 2 heads in 4 times ?
2)the probability of less than one head once?
3)the probability of more than 2 tails in 3 times ?
4)the expected number of two tails ?
5)the variance of the number of 2 heads
The probability of getting exactly two heads when two coins are tossed four times is 3/8 or 37.5%. This can be calculated by using the formula nCr = n! / (r!(n-r)!), where n is the total number of trials (4) and r is the number of successes (2).
There are 16 different outcomes possible when two coins are tossed four times. This can be calculated by using the formula 2^n, where n is the number of trials (4).
The probability of getting at least one head when two coins are tossed four times is 15/16 or 93.75%. This can be calculated by subtracting the probability of getting all tails (1/16) from 1.
Yes, the outcome of each coin toss is independent of the others. This means that the result of one coin toss does not affect the result of the other coin toss.
The expected number of heads when two coins are tossed four times is 2. This can be calculated by multiplying the number of trials (4) by the probability of getting a head (1/2).