They each had 900 dollars, so when combined they have 1800 dollars. They bought a movie ticket for 1200 dollars, so they now have 1800-1200=600 dollars.

600/2 is 300. Each bag of popcorn costs 200 dollars. So they could each buy 1.5 bags of popcorn.

5 0

2 years ago

Describe in detail how you would construct a 95% confidence interval for a set of 30 data points whose mean is 20 and population

postnew [5]

Answer:

We have been given confidence interval 95%, mean 20 , data set 30 and standard deviation 3.

We will use the formula: $mean\pm \frac{\sigma}{\sqrt{n}}\cdot (z-score)$

Here, $mean=20,\sigma=3,n=30,z-score=1.96$

Z-score value at 95% confidence interval is 1.96

On substituting the values in the formula to plug the values:

$20\pm\frac{3}{\sqrt{30}}\cdot (1.96)$

Now, we have a formula for marginal error: $z\cdot \frac{\sigma}{\sqrt{n}}$

Marginal error means your answer will be within that percentage only.

Say you have 3% marginal means your value will be within 3% real population 95% of the time.

7 0

4 years ago

The level of significance, α, is the probability of making a

Anna35 [415]

Answer:

type I error

Step-by-step explanation:

4 0

3 years ago