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.
The graph has a maximum value
Find the first semicircle area
Area semicircle can be determined by dividing the full area of circle by 2.
The first semicircle radius is 5 cm
semicircle area = 1/2 circle area
semicircle area = 1/2 × π × r²
semicircle area = 1/2 × 3.14 × 5²
semicircle area = 1/2 × 3.14 × 25
semicircle area = 39.25 cm²
Find the second semicircle area
Because the dimension of the second semicircle is congruent to the first semicircle, they have similar area measurement, 39.25 cm².
Find the quarter circle area
The area of quarter circle can be determined by dividing the full area of a circle by 4.
q circle = 1/4 × area of circle
q circle = 1/4 × π × r²
q circle = 1/4 × 3.14 × 10²
q circle = 1/4 × 314
q circle = 78.5 cm²
To find the entire area, add the area above together
area = first semicircle + second semicircle + q circle
area = 39.25 + 39.25 + 78.5
area = 157
The area of shaded region is 157 cm²
With a ratio, you should think of it in terms of a pie of sorts. In this example, the pie has 13 pieces, 9 of which consist of the perimeter of the large parallelogram and 4 of which consist of the perimeter of the smaller parallelogram. If we know that those 4 pieces of pie and equal to 20 units, then we would divide 20 by 4 to find the value of a single piece. 20/4=5 so a single piece of pie has a value of 5 units. We would then multiply 9 by 5 to find the value equivalent of the 9 pieces of pie. 9(5)=45. Therefore, the perimeter of the larger parallelogram is 45.