Answer:
38%
Step-by-step explanation:
Original price = $ 80
Price after reduction = $ 49.60
Reduction = 80 - 49.60 = $30.40
Percentage of decrease =
= 38%
Answer:
Step-by-step explanation:
A circumference of a circle can be determined by this: 2*pi*r
We're given the diameter. Divide that by 2 to get the radius.
6.45/2 = 3.225
Now multiply that by 2*pi. That gives us 2 * 3.14 * 3.225 = 20.253.
This could've also been done easier by doing pi*d where d is the diameter and you give the answer by multiplying them both. Also works, but the above formula is just key to many things and can also be used to derive the simpler one. Hope it helps! :)
Complete Question
The complete question is shown on the first uploaded image
Answer:
a
Yes the researcher can conclude that the supplement has a significant effect on cognitive skill
b
c
The result of this hypothesis test shows that there is sufficient evidence to that the supplement had significant effect.The measure of effect size is large due to the large value of Cohen's d (0.5778 > 0.30 )
Step-by-step explanation:
From the question we are told that
The sample size is n=16
The sample mean is
The standard deviation is
The population mean is
The level of significance is
The null hypothesis is
The alternative hypothesis is
Generally the test statistics is mathematically represented as
=>
=>
Generally the p-value is mathematically represented as
From the z-table
=>
=>
From the obtained values we see that
Decision Rule
Reject the null hypothesis
Conclusion
There is sufficient evidence to conclude that the supplement has a significant effect on the cognitive skill of elderly adults
Generally the Cohen's d for this study is mathematically represented as
=>
=>
The answer is the second one (B.)