A popular brand of light bulb is advertised as having a mean life of 1500 hours....
A popular brand of light bulb is advertised as having a mean life of 1500 hours. A sample of 40 of these bulbs provides an average life of 1428.3 hours. The researcher is interested in finding evidence at the .01 level that the mean life is lower than adverstised. Assume that the population standard deviation is 250 hours.
Which of the following hypotheses correct expresses the question of interest? H0: p=0.9, HA: p≠0.9 H0: μ≥1500, HA: μ<1500 H0: μ ≤1500, HA: μ >1500 H0: σ≤250, HA: σ<250 H0: σ≤250, HA: σ>250
What is the value of the test statistic?
What is the p-value (or any value in its range)?
Which of the following is(are) the correct critical value(s)?
|
-2.05 |
||
|
-1.96, 1.96 |
||
|
-2.58, 2.58 |
||
|
-2.33 |
||
|
2.426 |
What is the correct decision?
|
Don't Reject HA |
||
|
Reject H0 |
||
|
falafel |
||
|
Don't Reject H0 |
||
|
Reject HA |
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