Answer:
Step-by-step explanation:
n = 400
Proportion p = 229/400= 0.5725
For 95% confidence interval we use Z value as 1.96
Std error = 0.025
margin of error = 1.96*0.025
Confidence interval 95% = 0.5725±Margin of error
= (0.524, 0.621)
b) When smiled x becomes 277
p = 0.6925
Std error = 0.023
Margin of error= 1.96*0.023
Confidence interval = (0.647, 0.738)
Smiling increases the chances of stopping since mean and conidence interval bounds are showing increasing trend.
The given measurements determines zero triangles. Source: https://answers.yahoo.com/question/index?qid=20080804154329AA1gdUS
Answer:
yes .
Step-by-step explanation:
yes because the 7 percent is less than 2 dollars (1.4) , so her 20 dollars will be enough .
I don't know, what did the policeman shout to the math professor as a mob of excited calculus students crowded around these displays on his graphing calculator?
Answer:
(0.059, 0.133)
Step-by-step explanation:
Sample size = n = 250
Number of units which failed the test = x = 24
Proportion of units which failed the test =
= 0.096
Proportion of units which did not fail the test = q = 1 - p = 1 - 0.096 = 0.904
Confidence level = 95%
z-value for the confidence level = z = 1.96
The true proportion of the components that fail to meet the specification would be:

Using the values, we get:

Thus, 95% confidence interval estimate for the true proportion of components, p, that fail to meet the specifications is (0.059, 0.133)