Answer:
x = 15
Step-by-step explanation:
I am going to use the "butterfly" method for proportions
(there is another type of butterfly method that is different, I am not sure if there is another name for this method, sorry!)
Multiply the:
- top left by the bottom right
-the top right by the bottom left
and then:
- set them equal to each other
So we will <u>multiply 7 by x and 21 by 5</u> (if this doesn't make sense tell me and I will explain it even more!)
7x = 21 * 5
7x = 105
(Divide both sides by 7) <em>x = 15</em>
Hope this helps, have a nice day! :D <3
Answer:
0.288 < p < 0.338
Step-by-step explanation:
We have 2331 adults polled and 730 said they believe in UFOs. We are to construct a 99% confidence interval for the population proportion. We are told to round to 3 decimal places as needed.
We need to find p-hat and q-hat
p-hat = 730/2331 = 0.313
q-hat = 1 - p-hat = 1 - 0.313 = 0.687
Since the sample size is greater than 30, we use a z-value for 99% confidence, which is 2.575
See attached photo for the construction of the confidence interval
Answer:
The probability that a jar contains more than 466 g is 0.119.
Step-by-step explanation:
We are given that a jar of peanut butter contains a mean of 454 g with a standard deviation of 10.2 g.
Let X = <u><em>Amount of peanut butter in a jar</em></u>
The z-score probability distribution for the normal distribution is given by;
Z = ~ N(0,1)
where, = population mean = 454 g
= standard deviation = 10.2 g
So, X ~ Normal()
Now, the probability that a jar contains more than 466 g is given by = P(X > 466 g)
P(X > 466 g) = P( >
) = P(Z > 1.18) = 1 - P(Z
1.18)
= 1 - 0.881 = <u>0.119</u>
The above probability is calculated by looking at the value of x = 1.18 in the z table which has an area of 0.881.