1) It is known that a laboratory task takes the average person 2.5 seconds. A researcher was interested in whether older people are slower (take longer) on this task. The researcher tested 30 randomly selected 80-year-olds. Their mean time was 2.7 seconds, with an estimated population standard deviation of 1.4 seconds. What should the researcher conclude (use the .05 level)? a. /2 Identify the populations involved: population 1 = _____________________________________________________________________ population 2 = _____________________________________________________________________ b. /2 State the research and null hypothesis: Research Hypothesis = _____________________________________________________________ Null Hypothesis = _________________________________________________________________ c. /6 Determine the characteristics of the comparison distribution (hint: it is a distribution of means): mean of the distribution of means = degrees of freedom = estimated population variance = estimated population standard deviation = variance of the distribution of means = standard deviation of distribution of means = d. /1 Cutoff sample score on the comparison distribution at which we’ll reject H0 (hint: 1 or 2 tails?) = e. /1 Determine your sample’s score on the comparison distribution = f. /1 Accept or reject the null hypothesis? g. /4 Sketch the distributions involved:
Answer:
K
Step-by-step explanation:
The term "K" can be used in place of thousand, such as 5k
Hope this helps you out!
~theLocoCoco
The ages of the crew, Marty and Blakeley are 32 years, 48 years and 24 years respectively.
<h3>Algebra</h3>
- Crew's age = x
- Marty's age = 1.5x
- Blakely's age = 0.75x
Total = crew's age + Marty's age + blakely's age
104 = x + 1.5x + 0.75x
104 = 3.25x
x = 104 ÷ 3.25
x = 32 years
Therefore,
Crew's age = x
= 32 years
Marty's age = 1.5x
= 1.5(32)
= 48 years
Blakely's age = 0.75x
= 0.75(32)
= 24 years
Learn more about algebra:
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A is 0.0028
and B is 0.054
Step-by-step explanation:
4x+28=5x+8
x=20
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