Answer:
Step-by-step explanation:
The null hypothesis is:
H0: μ(1995)=μ(2019)
The alternative hypothesis is:
H1: μ(1995)<μ(2019)
Because Roger wants to know if mean weight of 16-old males in 2019 is more than the mean weight of 16-old males in 1995 the test only uses one tail of the z-distribution. It is not a two-sided test because in that case the alternative hypothesis would be: μ(1995)≠μ(2019).
To know the p-value, we use the z-statistic, in this case 1.89 and the significance level. Because the problem does not specify it, we will search for the p-value at a 5% significance level and at a 1%.
For a z of 1.89 and 5% significance level, the p-value is: 0.9744
For a z of 1.89 and 1% significance level, the p-value is: 0.9719
Answer:
The reading speed of a sixth-grader whose reading speed is at the 90th percentile is 155.72 words per minute.
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:

What is the reading speed of a sixth-grader whose reading speed is at the 90th percentile
This is the value of X when Z has a pvalue of 0.9. So it is X when Z = 1.28.




The reading speed of a sixth-grader whose reading speed is at the 90th percentile is 155.72 words per minute.
Answer:
16 years
Step-by-step explanation:
1.7% of 2000 is $34
$544 divided by $34 = 16 years, that is if the interest is yearly and not monthly though
Answer:
5.19
Step-by-step explanation:
first do 28.86 / 6 to find out how much each paid. then subtract that number (4.81) from 10
Please don't ask 2 questions in 1 question
remember that percent is parts out of 100 so x%=x/100
basically just remove the percent sign and move the decimal place 2 places to the left to convert to fraction
the first one
20 dollars
4.75% tax
15% tip
it depends if you want to tip on the total with tax or without tax
it is better to top on the without-tax value since tax comes from you so
find 4.75% of 20 and add that to 15% of 20 then add that to 20 to get the proper value
scenarios
1. 20+(20 times 4.75%)+(20 times 15%)=23.95
2. ([(20 times 104.75%)] times 115%)=24.09
both are bellow $25 so $25 shoudl be enough to cover it
total cost of a spa treatment of 42 with 6% tax and 20% tip
so you could again do two things:
1. apply tax and give tip on the new amount
2. find the tip and add that to the tax of only 42
scenarios:
1.(42 times 106%) times 120%=$50.4
2. (42 times 20%) +(42 times 106%)=$52.92
it depens on what you tip on