<h2><u>
Answer with explanation</u>
:</h2>
Let
be the distance traveled by deluxe tire .
As per given , we have
Null hypothesis : 
Alternative hypothesis : 
Since
is left-tailed and population standard deviation is known, thus we should perform left-tailed z-test.
Test statistic : 
where, n= sample size
= sample mean
= Population mean
=sample standard deviation
For
, we have

By using z-value table,
P-value for left tailed test : P(z≤-2.23)=1-P(z<2.23) [∵P(Z≤-z)=1-P(Z≤z)]
=1-0.9871=0.0129
Decision : Since p value (0.0129) < significance level (0.05), so we reject the null hypothesis .
[We reject the null hypothesis when p-value is less than the significance level .]
Conclusion : We do not have enough evidence at 0.05 significance level to support the claim that t its deluxe tire averages at least 50,000 miles before it needs to be replaced.
Answer: b=4
Step-by-step explanation: Let's solve your equation step-by-step.
4b+5=1+5b
Step 1: Simplify both sides of the equation.
4b+5=5b+1
Step 2: Subtract 5b from both sides.
4b+5−5b=5b+1−5b
−b+5=1
Step 3: Subtract 5 from both sides.
−b+5−5=1−5
−b=−4
Step 4: Divide both sides by -1.
−b
−1
=
−4
−1
b=4
Answer:
D
Step-by-step explanation:
hihihihihuiuiijihihihihihihih