The discount on a new refrigerator was $190. This was a discount of 11 %.

The average time a subscriber spends reading The Wall Street Journal is 49 minutes (The Wall Street Journal Subscriber Study). A

erica [24]

Answer:

$P(X>60)=P(\frac{X-\mu}{\sigma}>\frac{60-\mu}{\sigma})=P(Z>\frac{60-49}{16})=P(z>0.6875)$

And we can find the probability with the complement rule and the normal standard distirbution and we got:

$P(z>0.6875)=1-P(z$

Step-by-step explanation:

Let X the random variable that represent the time spent reading of a population, and for this case we know the distribution for X is given by:

$X \sim N(49,16)$

Where $\mu=49$ and $\sigma=16$

We are interested on this probability

$P(X>60)$

And we can use the z score formula given by:

$z=\frac{x-\mu}{\sigma}$

Using this formula we got:

$P(X>60)=P(\frac{X-\mu}{\sigma}>\frac{60-\mu}{\sigma})=P(Z>\frac{60-49}{16})=P(z>0.6875)$

And we can find the probability with the complement rule and the normal standard distirbution and we got:

$P(z>0.6875)=1-P(z$

5 0

3 years ago

Someone help lol thx

emmainna [20.7K]

Answer:

which question? you want me to answer

Step-by-step explanation:

7 0

2 years ago

Read 2 more answers

Answel

LiRa [457]

22 rides would be needed Explanation: one ride takes 6 kids and there are 130 kids 20 rides would take 120 21 rides would take 126 and since you can’t have kids without a ride and you can’t cut a ride into pieces there must be 22 rides

3 0

3 years ago

TV studio has brought in 9 boy kittens and 6 girl kittens for a cat food commercial. The director is going to choose 9 of these

Amanda [17]

Answer:

probability = 0.2517

Step-by-step explanation:

given data

boy kittens = 9

girl kittens = 6

choose kittens at random = 9

solution

total kitten are = 9 + 6 = 15

first we get here total no of probability that is

n(s) = 15 C 9

n(s) = $\frac{15!}{9!(15-9)!}$

n(s) =5005

and

total way to chose 5 boy kittens is = 9 C 3

n(3) = $\frac{9!}{3!(9-3)!}$

n(3) = 84

and

total way to chose 4 girl kittens is = 6 C 4

n(4) = $\frac{6!}{4!(6-4)!}$

n(4) = 15

so

total way to chose 5 boy kittens and 4 girl kittens is

total way = 84 ×15 = 1260

so probability that the director chooses 5 boy kittens and 4 girl kittens is

probability = $\frac{1260}{5005}$

probability = 0.2517

6 0

3 years ago

. A used car dealer says that the mean price of a two-year old sedan (in good condition) is at least $20,500. You suspect this c

Taya2010 [7]

Answer: There is sufficient evidence to reject the dealer's claim that the mean price is at least $20,500

Step-by-step explanation:

given that;

n = 14

mean Ж = 19,850

standard deviation S = 1,084

degree of freedom df = n - 1 = ( 14 -1 ) = 13

H₀ : ц ≥ 20,500

H₁ : ц < 20,500

Now the test statistics

t = (Ж - ц) / ( s/√n)

t = ( 19850 - 20500) / ( 1084/√14)

t = -2.244

we know that our degree of freedom df = 13

from the table, the area under the t-distribution of the left of (t=-2.244) and for (df=13) is 0.0215

so P = 0.0215

significance ∝ = 0.05

we can confidently say that since our p value is less than the significance level, we reject the null hypothesis ( H₀ : ц ≥ 20,500 )

There is sufficient evidence to reject the dealer's claim that the mean price is at least $20,500

6 0

3 years ago