Question

A simple random sample of 100 adults is obtained, and each person’s red blood cell count (in cells per microliter) is measured. The sample mean is 5.22 and the sample standard deviation is 0.53. Use a 0.01 significance level to test the claim that the sample is from a population with a mean less than 5.3, the calculated value of t-test statistic is (Given that H0: µ = 5.3, Ha:µ < 5.3)

choose

-15.09

15.09

-1.509

1.509

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Three students took a statistics test before and after coaching, but coaching did not effect the scores of students i.e mean change in scores is zero. Their scores are as follows:

Students	A	B	C
Before	71	88	63
After	70	89	60

The value of t-test statistic for matched pairs is

choose

8.66

0.866

-0.866

-8.66

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The basic procedure of hypothesis testing is to make an initial assumption about the population parameter, collect evidence and decide whether to "reject" or "not reject" our initial assumption.

choose

True

False

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Answer 1

1)

population mean μ=	5.3
sample mean 'x̄=	5.220
sample size   n=	100.00
sample std deviation s=	0.530
std error 'sx=s/√n=	0.0530
test stat t ='(x-μ)*√n/sx=	-1.509

2)

S. No	before	after	diff:(d)=x1-x2	d2
1	71	70	1	1.00
2	88	89	-1	1.00
3	63	60	3	9.00
	total	=	Σd=3	Σd2=11
	mean dbar=	d̅                           =	1.0000
	degree of freedom =n-1                            =		2.000
	Std deviaiton SD=√(Σd2-(Σd)2/n)/(n-1) =		2.0000
	std error=Se=SD/√n=		1.1547
	test statistic            =	(d̅-μd)/Se         =	0.8660

3)

true