Find two numbers with a sum of 20 and a difference of 14
Make two equations
X+Y=20
X-Y=14
Now add x since y cancels out and add 20+14 To end up with
2x=34
Now divide 2 both sides to get x alone
2x/2=34/2
X=17
Now substitute x answer to first equation and solve for y
17+y=20
Subtract 17 both sides
Y= 3
Your two numbers are
3 and 17
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

=> 
=> 
Answer:
-72 and -77
Step-by-step explanation:
-149 divided by 2 is 74.5 and sense we want a 5 difference we divide 5 by 2 to get 2.5 the we take 74.5 and add 2.5 to get - 72 and take 74.5 and subtract 2.5 to get -77.
The answer is 14. if n equals 3 and you use the equation instead of n. 3+11 that would equal 14
C is the answer
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