statistics

posted by .

suppose 25% of the urban population is 18 years old or younger. five residents of that city are selected at random find the probability that at least two of the selected five persons are 18 years old or younger. please help me with this question !!!

• statistics -

Here's one way to do this problem:

n = 5
p = .25
q = 1 - p = 1 - .25 = .75

You can do this: you can find P(0) and P(1), add both values together, then subtract from 1.

You can use a binomial probability table, or calculate by hand using the following formula:
P(x) = (nCx)(p^x)[q^(n-x)]

I hope this will help.

Similar Questions

1. college math - biostatistics

hey... first time user and really lost. wondering if someone can help: Based on data from the Statistical Abstract of the United States, 112th Edition, only about 14% of senior citizens (65 years old or older) get the flu each year. …
2. algebra

A person is 3 times as old as aonther person but in 15 years she will only be 2 times as old. I found the answer the younger person is 15 years old and the older person is 45 years old. But 15 years from now the younger person will …
3. statistics

Sweden is reported to have among the highest percentage of citizens aged 80 years and over, at approximately 5.5 % (i.e. 5.5 % of it's population falls within this age category). Suppose 20 individuals are randomly selected from the …
4. statistics

Based on data from a statistical abstract, only about 12% of senior citizens (65 years old or older) get the flu each year. However, about 24% of the people under 65 years old get the flu each year. In the general population, there …
5. statistics

A study was conducted to count the different age groups of kids that usually play in a park on a Sunday morning. The following data was collected Years Old Number of Kids 1 3 2 22 3 8 4 16 5 9 a) List the simple events of the experiment. …
6. statistics

A study was conducted to count the different age groups of kids that usually play in a park on a Sunday morning. The following data was collected Years Old Number of Kids 1 3 2 22 3 8 4 16 5 9 a) List the simple events of the experiment. …
7. finite math

The probability that a 3-year old garter snake will reach 4 years old is 0.94461. (a) what is the probability that two randomly selected will reach 4 years old?
8. finite math

The probability that a 3-year old garter snake will reach 4 years old is 0.62719. (a) what is the probability that two randomly selected will reach 4 years old?
9. finite math

The probability that a 3-year old garter snake will reach 4 years old is 0.62719. (a) what is the probability that two randomly selected will reach 4 years old?
10. Statistics

The probability that a randomly selected two-year-old male stinkbug will live to be three years old is .59963 what is the probability that to randomly selected two-year-old male stinkbugs will live to be three years old?

More Similar Questions