Answer:
The minimum height in the top 15% of heights is 76.2 inches.
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 problem, we have that:

Find the minimum height in the top 15% of heights.
This is the value of X when Z has a pvalue of 0.85. So it is X when Z = 1.04.




The minimum height in the top 15% of heights is 76.2 inches.
Answer:
The bill excluding tax is $31.21 and the 20% tip was $6.24.
Answer: b
Step-by-step explanation: cause I know the answer/ i did the quiz
Pergunta correta:
Seja 17x + 51y = 102. Qual é o valor de 9x + 27a? (A) 54 (B) 36 (C) 34 (D) 18 (E) indeterminado
Resposta: A) 54
Explicação passo a passo:
17x + 51y = 102 - - - - equação 1
Divulgue até 17
x + 3y = 6 - - - - - - - Equação 2
9x + 27y - - - - - - - equação 3
Comparando as equações 2 e 3
(Equação 3) = 9 × (equação 2)
Isso é, 9x + 27y = 9 × (x + 3y = 6)
9x + 27y = 9x + 27y = 54
Portanto ; 9x + 27y = 54
Answer:
The 80% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.149, 0.207).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
Suppose a sample of 292 tenth graders is drawn. Of the students sampled, 240 read above the eighth grade level.
So 292 - 240 = 52 read below or at eight grade level, and that 
80% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

The 80% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.149, 0.207).