Answer:
The claim is not true
Step-by-step explanation:
We are given that A local retailer claims that the mean waiting time is less than 8 minutes.


A random sample of 20 waiting times has a mean of 6.3 minutes with a standard deviation of 2.1 minutes.

s = 2.1
n = 20
Since n <30 and population standard deviation is unknown
So,we will use t test
So,

t=-3.62
α = 0.01
Degree of freedom = df=n-1=20-1=19

t calculated < t critical
So, we failed to reject null hypothesis
Hence the claim is not true
Answer:
5
Step-by-step explanation:
When you have a negative next to a negative, you can turn it into a positive. For example the -(-8) would now be +8. This is called the airplane strategy because it forms a airplane if you flip you sheet of paper or your device.
From here, we have -3+8.
Now we subtract since each value has a different sign and we get +5.
Hope this helps!! :)
[C] 0.05b + 0.25s + 0.4n = 20
b = balloons
s = streamers
n = noisemaker
Since they already give us the price of each item we just need to add a variable at the end of each one since we don't know how many of each item is bought. Adding the costs of all the party supplies should not go over $20. We can automatically eliminate B and D. We can also eliminate A because the prices of each item are incorrect. Therefore, C is the correct answer.
Best of Luck!
Answer: 
Step-by-step explanation:




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