x,z,y = 20,15,-33
i think thats it im sorry
Answer:
(A) With 99% confidence, the proportion that favours the Green initiative is between 418.895 and 423.105 (no approximation; answers were gotten exactly in 3 decimal places).
(B) If many groups of 593 (greater than the initial sample size of 556) randomly selected Americans were surveyed then a different confidence interval would be used or produced from each group.
About 90% of these confidence intervals will contain the true population proportion of Americans who favour the Green initiative and about 10% will not contain the true population proportion.
Step-by-step explanation:
(A) 99% of 421 = 416.79
421 - 416.79 = 4.21
4.21 ÷ 2 = 2.105
(421-2.105), (421+2.105)
The lower and upper limits are:
[418.895 , 423.105]
(B) A wider confidence interval such as 90% will be better suited in a case of multiple samples like this.
Answer:
The inter-decile range of IQ is 40.96.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean and standard deviation , the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:
First decile:
100/10 = 10th percentile, which is X when Z has a pvalue of 0.1. So it is X when Z = -1.28.
Ninth decile:
9*(100/10) = 90th percentile, which is X when Z has a pvalue of 0.9. So it is X when Z = 1.28.
Interdecile range:
120.48 - 79.52 = 40.96
The inter-decile range of IQ is 40.96.
Answer:
$218.70
Step-by-step explanation:
You need to first convert the percentage to the decimal.
20% = 0.2
Now, you need to find 20% of each bill by multiplying each bill by 0.2.
0.2(185.45) + 0.2(205.20) + 0.2(195.05) + 0.2(245.80) + 0.2(262.00)
Because of the distributive property, you can add up the bills and multiply the sum by 0.2.
0.2(185.45 + 205.20 + 195.05 + 245.80 + 262.00)
0.2(1093.50)
218.7
The waiter made $218.70 in tips.
Answer:
Step-by-step explanation: