Step-by-step explanation:
here's the answer to your question
<h2><u>
Answer with explanation</u>
:</h2>
Let
be the average life of light bulbs.
As per given , we have
Null hypothesis : 
Alternative hypothesis : 
Since
is right-tailed and population standard deviation is also known, so we perform right-tailed z-test.
Formula for Test statistic : 
where, n= sample size
= sample mean
= Population mean
=population standard deviation
For
, we have

Using z-value table , Critical one-tailed test value for 0.06 significance level :

Decision : Since critical z value (1.5548) < test statistic (1.6180), so we reject the null hypothesis .
[We reject the null hypothesis when critical value is less than the test statistic value .]
Conclusion : We have enough evidence at 0.06 significance level to support the claim that the new filament yields a longer bulb life
Answer:
25. a = 60
26. a = 17
Step-by-step explanation:
In these two problems we are going to use a property of parallelograms that says: opposite angles have equal measure
so we have
25.

and for 26 we have

Answer:
1:4 or 1/4
Step-by-step explanation:
9 cm : 36 cm
They both can be divided by 9 so,
9 ÷ 9 : 36 ÷ 9
= 1 : 4
Hope this helps
Answer:
8.6
Step-by-step explanation: