Trinomial+binomial = what

A sign company charges $28 per yard for each custom made banner. Ms gill orders 2 banners that are each 17/8 yards long and 1 ba

vampirchik [111]

You start by writing your expression. Since each banner cost 28 per yard, you're going to multiply the price by the length by the number of banners she bought. (28)(17/8)(2)+(28)(25/8)=206.50

7 0

3 years ago

According to a study, 50 % of adult smokers started smoking before 21 years old. 5 smokers 21 years old or older are randomly se

belka [17]

Answer:

a) The probability that at least 2 of them started smoking before 21 years of age is 0.1875 = 18.75%.

b) The probability that at most 4 of them started smoking before 21 years of age is 0.96875 = 96.875%.

c) The probability that exactly 3 of them started smoking before 21 years of age is 0.3125 = 31.25%.

Step-by-step explanation:

For each smoker, there are only two possible outcomes. Either they started smoking before 21 years old, or they did not. Smokers are independent, which means that the binomial probability distribution is used to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

In which $C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

And p is the probability of X happening.

50% of adult smokers started smoking before 21 years old.

This means that $p = 0.5$

5 smokers 21 years old or older are randomly selected, and the number of smokers who started smoking before 21 is recorded.

This means that $n = 5$ .

a) The probability that at least 2 of them started smoking before 21 years of age is

This is:

$P(X \geq 2) = 1 - P(X < 2)$

In which

$P(X < 2) = P(X = 0) + P(X = 1)$

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 0) = C_{5,0}.(0.5)^{0}.(0.5)^{5} = 0.03125$

$P(X = 1) = C_{5,1}.(0.5)^{1}.(0.5)^{4} = 0.15625$

$P(X < 2) = P(X = 0) + P(X = 1) = 0.03125 + 0.15625 = 0.1875$

The probability that at least 2 of them started smoking before 21 years of age is 0.1875 = 18.75%.

b) The probability that at most 4 of them started smoking before 21 years of age is

This is:

$P(X \leq 4) = 1 - P(X = 5)$

In which

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 5) = C_{5,5}.(0.5)^{5}.(0.5)^{0} = 0.03125$

$P(X \leq 4) = 1 - P(X = 5) = 1 - 0.03125 = 0.96875$

The probability that at most 4 of them started smoking before 21 years of age is 0.96875 = 96.875%.

c) The probability that exactly 3 of them started smoking before 21 years of age is

This is P(X = 3). So

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 3) = C_{5,3}.(0.5)^{3}.(0.5)^{2} = 0.3125$

The probability that exactly 3 of them started smoking before 21 years of age is 0.3125 = 31.25%.

4 0

2 years ago

Lincoln Middle School plans to collect more than 2000 cans of food in a food drive. So far, 668 cans have been collected. Write

Schach [20]

Let x be the unknown number.

7x + 668 < 2000 => 7x plus 668 is less than 2000

where:
7x => x represents the number of cans to be collected in 7 days
668 is the number of cans already collected.
2000 is the target number of cans.

7x + 668 < 2000
 - 668 -668
7x < 1332
÷7 ÷7
x < 190.30
or
x < 190

To check:

7x + 668 < 2000
7(190) + 668 < 2000
1330 + 668 < 2000
1998 < 2000

6 0

3 years ago

4x-4y=15 whats the slope

Reika [66]

Hey there!!!

What is slope-intercept form ?

The slope intercept form is y = mx + b

Where 'm' is the slope and 'b' is the y-intercept.

Given equation :

... 4x - 4y = 15

This is given is standard form.

Let's convert this into slope-intercept form.

... 4x - 4y = 15

... -4y = -4x + 15

... y = x + ( 15 / 4 )

Hence, the slope is '1'.

Hope my answer helps!

4 0

3 years ago

Grace took 35 minutes to bicycle east to her friends house a total of 4 kilometers was her velocity in km/min

Snowcat [4.5K]

She took 4 miles 4 times 4 is what and then that’s your answer

5 0

3 years ago