Answer:
a. H0:μ1≥μ2
Ha:μ1<μ2
b. t=-3.076
c. Rejection region=[tcalculated<−1.717]
Reject H0
Step-by-step explanation:
a)
As the score for group 1 is lower than group 2,
Null hypothesis: H0:μ1≥μ2
Alternative hypothesis: H1:μ1<μ2
b) t test statistic for equal variances
t=(xbar1-xbar2)-(μ1-μ2)/sqrt[{1/n1+1/n2}*{((n1-1)s1²+(n2-1)s2²)/n1+n2-2}
t=63.3-70.2/sqrt[{1/11+1/13}*{((11-1)3.7²+(13-1)6.6²)/11+13-2}
t=-6.9/sqrt[{0.091+0.077}{136.9+522.72/22}]
t=-3.076
c. α=0.05, df=22
t(0.05,22)=-1.717
The rejection region is t calculated<t critical value
t<-1.717
We can see that the calculated value of t-statistic falls in rejection region and so we reject the null hypothesis at 5% significance level.
It should be letter D positive 1
The last line answer ur second qn and the above ate examples
Answer:
x=−3 and y=7
Step-by-step explanation Solve: 7x+2y=−7for x:
7x+2y=−7
7x+2y+−2y=−7+−2y(Add -2y to both sides)
7x=−2y−7
7x
7
=
−2y−7
7
(Divide both sides by 7)
x=
−2
7
y−1
------------
−2
7
y−1forxin11x+5y=2:
11x+5y=2
11(
−2
7
y−1)+5y=2
13
7
y−11=2(Simplify both sides of the equation)
13
7
y−11+11=2+11(Add 11 to both sides)
13
7
y=13
13
7
y
13
7
=
13
13
7
(Divide both sides by 13/7)
y=7
------------------------
Substitute7foryinx=
−2
7
y−1:
x=
−2
7
y−1
x=
−2
7
(7)−1
x=−3(Simplify both sides of the equation)
