In a certain country, the true probability of a baby being a boy is 0.511. Among the next eight randomly selected births in the country, what is the probability that at least one of them is a girl?

The probability that at least one of 8 babies born is a girl  is 0.9954.

Step-by-step explanation:

Let X = a baby born is a girl.

The probability of a baby born being a girl is,

P (G) = 1 - P (B)

        = 1 - 0.511

     p  = 0.489

The number of births is, n = 8.

The random variable X follows a Binomial distribution with parameters n and p.

The probability mass function of the Binomial distribution is:

Compute the probability that out of 8 births at least one is a girl as follows:

P (X ≥ 1) = 1 - P (X < 1)

             = 1 - P (X = 0)

Thus, the probability that at least one of 8 babies born is a girl  is 0.9954.

3

step-by-step explanation:

in standard form:

a= dictionaries

b= maps

you have to buy 3 dictionaries, so put a 3 next to the a (dictionaries) so that you can multiply them by each other.

a3+b= 60 (the amount of money you have)

we already know the cost of a=15 so replace a with $15

($15 x 3)+b=60

multiply 15 and 3 to get $45 and replace it with $45

45+b=60

and then replace b with 15 to get the total:

45+15=60

that means you have $15 left after buying 3 dictionaries.

15 divided by the cost of a map ($5) equals 3.

so you can buy 3 maps.

sorry if it was confusing!

step-by-step explanation:

i'm pretty sure it would take 20 hours because it's half the men so you multiply the number of hours it takes by 2