Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

The spring for a prosthetic foot you are designing needs to be 2 cm in length. Y

ID: 3273940 • Letter: T

Question

The spring for a prosthetic foot you are designing needs to be 2 cm in length. You randomly sample 36 springs from a supplier and find their lengths to be 2.03 cm on average, with a standard deviation of +/- .1 cm. Is there cause for concern that your supplier is systematically designing springs that are different than your specifications?

Yes because I get a one-sample t value of 1.8. Since the critical value of t (2-tailed) at alpha = .05 is equal to right around 2.03, and 1.8 is less than this critical value, I MUST reject the null hypothesis that the sample comes from the referent population.

No because I get a one-sample t value of 1.8. Since the critical value of t (2-tailed) at alpha = .05 is equal to right around 2.03, and 1.8 is less than this critical value, I CANNOT reject the null hypothesis that the sample comes from the referent population.

Neither A nor B

A & B

A.

Yes because I get a one-sample t value of 1.8. Since the critical value of t (2-tailed) at alpha = .05 is equal to right around 2.03, and 1.8 is less than this critical value, I MUST reject the null hypothesis that the sample comes from the referent population.

B.

No because I get a one-sample t value of 1.8. Since the critical value of t (2-tailed) at alpha = .05 is equal to right around 2.03, and 1.8 is less than this critical value, I CANNOT reject the null hypothesis that the sample comes from the referent population.

C.

Neither A nor B

D.

A & B

Explanation / Answer

Given that,

population mean(u)=2

sample mean, x =2.03

standard deviation, s =0.1

number (n)=36

null, Ho: =2

alternate, H1: !=2

level of significance, = 0.05

from standard normal table, two tailed t /2 =2.03

since our test is two-tailed

reject Ho, if to < -2.03 OR if to > 2.03

we use test statistic (t) = x-u/(s.d/sqrt(n))

to =2.03-2/(0.1/sqrt(36))

to =1.8

| to | =1.8

critical value

the value of |t | with n-1 = 35 d.f is 2.03

we got |to| =1.8 & | t | =2.03

make decision

hence value of |to | < | t | and here we do not reject Ho

p-value :two tailed ( double the one tail ) - Ha : ( p != 1.8 ) = 0.0805

hence value of p0.05 < 0.0805,here we do not reject Ho

ANSWERS

---------------

null, Ho: =2

alternate, H1: !=2

test statistic: 1.8

critical value: -2.03 , 2.03

decision: do not reject Ho

p-value: 0.0805

B.

No because I get a one-sample t value of 1.8. Since the critical value of t (2-tailed) at alpha = .05 is equal to right around 2.03, and 1.8 is less than this critical value, I CANNOT reject the null hypothesis that the sample comes from the referent population.

Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
Chat Now And Get Quote