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.
Answer:
both are equal
Step-by-step explanation:
there are two side tails and heads so there a 1/2 chance it will land on heads
Answer:
9
Step-by-step explanation:
<em>Degrees of freedom</em> is the number of values in the final calculation of a statistic that are free to vary. Degrees of freedom are related to sample size and calculated by n-1 where n is the <em>sample size</em>.
The Supervisor selects 10 teddy bears as sample from 5000 teddy bears produced daily. Therefore in this situation, there are 10-1=9 degrees of freedom
Answer:
The numbers are 19 and 71.
Step-by-step explanation:
Let x and y represent the two numbers. Then x + y = 90.
Also, if we assume that the larger number is y, then y = 3x + 14.
We must solve this system of linear equations. Since we already have the result of solution for y (y = 3x + 14), let's use the substitution method to find the solution:
x + y = 90 becomes x + 3x + 14 = 90, or:
4x = 76. Thus, x = 76/4, or 19. If x = 19, then y = 3(19) + 14, or y = 71.
The numbers are 19 and 71.
Note that these add up to 90, as they must, and that 71 is 14 more than 3 times 19.
Lynn mixes 39 pounds of water with 48 pounds of brick dust, so the mixture has a total weight of 39 + 48 = 87 pounds.
13 pounds are spilled during mixing, so she's left with 87 - 13 = 74 pounds to turn into bricks.
7 pounds are needed for 1 brick, so she can make 10 bricks because 7 • 10 = 70 and 7 • 11 = 77, and 70 < 74 < 77.
If she uses the mixture to make 10 bricks, she uses up 70 pounds of it, which leaves 4 pounds to be washed out.