Answer:

Step-by-step explanation:
The firm tests 75 parts, and finds that 0.25 of them are notusable
n = 75
x = 0.25 \times 75 = 18.75≈19



Confidence level = 95%
So, Z_\alpha at 95% = 1.96
Formula of confidence interval of one sample proportion:


Confidence interval 
Answer:
0.05357142
Step-by-step explanation:
Answer: 33
explanation: 100/3 = 33.333, and since it isn't possible for 0.333 to be three different students being picked, there are only 33 different ways.
There is no picture for me to check
Answer: 20.52
Step-by-step explanation:
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