Answer:
0.226, 0.374
Step-by-step explanation:
A high school is running a campaign against the over-use of technology in teens. The committee running the campaign decides to look at the difference in social media usage between teens and adults. and then Find a 90% confidence interval for the difference in proportions.
The formula for confidence interval for the difference between the proportions is given as:
p1 - p2 ± z × √p1 (1 - p1)/n1 + p2(1 - p2)/n2
From the question
We have two groups.
Group 1
They take a random sample of 200 teens in their city (Group 1) and find that 85% of them use social media,
p1 = x/n1
n1 = 200
x1 = 85% × 200 = 170
p1 = 170/200
p1 = 0.85
Group 2
Take another random sample of 180 adults in their city (Group 2) and find that 55% of them use social media.
p2 = x/n1
n2= 180
x2 = 55% × 180 = 99
p2 = 99/180
p2 = 0.55
z = z score for 90% Confidence Interval = 1.645
p1 - p2 ± z × √p1 (1 - p1)/n1 + p2(1 - p2)/n2
= 0.85 - 0.55 ± 1.645 √0.85(1 - 0.85)/200 + 0.55(1 - 0.55)/180
= 0.85 - 0.55 ± 1.645 √0.85(0.15)/200 + 0.55(0.45)/180
= 0.30 ± 1.645 × √0.0020125
= 0.30 ± 1.645 × 0.0448608961
= 0.30 ± 0.0737961741
Hence
= 0.30 - 0.0737961741
= 0.2262038259
= 0.30 + 0.0737961741
= 0.3737961741
Therefore, 90% confidence interval for the difference in proportions is (0.226, 0.374
Answer:
Step-by-step explanation:
h(t)=-16t+128t+1040
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HELP MY THING WONT WORK SORRY
According to order of operations rules, exponentiation must be done first. Thus, we have
(3^2)*(3^2) = (9)(9) = 81.
Alternatively, note that there's only one base (3) here, even tho' it shows up more than once. So, 3^2*3^2 = 3^(2+2) = 3^4 = 81.
All you have to do is add the number to the variable you need to. It works the same for subtraction instead you will put y-14 or any variable and number that is needed to subtract from it and remember when they say a number more than a variable it is + that number if they say a number less than a variable it is - that number .
y+14
Complete Question
According to the Bureau of Labor Statistics, citizens remain unemployed for an average of 15.9 weeks before finding their next job (June, 2008). Suppose you want to show that Louisiana has been effective in getting their unemployed back to work sooner. You take a random sample of 50 citizens who were unemployed six months earlier and ask them to report the duration. You find that the average time spent unemployed was 13.4 weeks with a sample standard deviation of the time unemployed is 6.7 weeks.
1 Which of the following statements is the correct alternative hypothesis?
2 The test statistic for testing the hypothesis is
a. -2.64
b. -2.32
c. -2.11
d. -1.28
e. none of these are correct
Answer:
1
The alternative hypothesis
2
The test statistics
Step-by-step explanation:
From the question we are told that
The population mean value for time citizens remain unemployed is
The sample size is n = 50
The sample standard deviation is 6.7 weeks.
The sample mean value for time citizens remain unemployed is
The null hypothesis is
The alternative hypothesis
Generally test statistics is mathematically represented as
=>
=>