Question

1.- Statewide, the average score on the verbal portion of the college entrance exam is 453. with a standard deviation of 95. Arandom sample of 137 seniors at Littlewood Regional High School shows a mean score of 502. Is there a significant difference? Alpha level:.10 a) The null and alternate hypothesis b) stablish the critical region: c) Compute the statistics d) Make a decision and conclusion

Thank you so much in advance for your help! :)

Answer 1

Ans:

a)

$H_0:\mu =453$

$H_a:\mu\neq 453$

b)

alpha=0.1

critical z values=+/-1.645

Reject H₀ if z<-1.645 or z>1.645

c)

Test statistic:

z=(502-453)/(95/SQRT(137))

z=6.04

d)

As,z>1.645,Reject the null hypothesis.

There is sufficient evidence to conclude that mean score is significantly different from 453.