Answer:
-8b + 9 - 5k
Step-by-step explanation:
I am assuming the blue highlighted portion is your answer, and is not a part of the initial question
(-4b + 15 - 7k) - (6 + 4b - 2k)
Combine like terms
-4b - + 4b
Negative + Positive = Negative
-4b - 4b = -8b
15 - 6 = 9
-7k - - 2k
Negative + Negative = Positive
-7k + 2k = -5k
Put them all together:
0b + 9 - 5k
Simplify
-8b + 9 - 5k
I got the same answer as you (just in a different order)
Answer:
Step-by-step explanation:
Si haces una fracción buscando su denominador te da resultados
Can you please explain more? I don’t get what you mean.....
Answer: c. z = 1.35; Reject the null hypothesis
Step-by-step explanation:
Let 
be the average life expectancy of its batteries.
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.
Test statistic : 
where, n= sample size
= sample mean
= Population mean
=population standard deviation
For 
, we have
Critical one-tailed test value for 0.10 significance level :
Decision : Since critical z value (1.28) < test statistic (1.35), so we reject the null hypothesis .
[When critical value is less than the test statistic value , we reject the null hypothesis .]
This question doesn’t make sense, double check you wrote it right
