Let's simplify step-by-step.<span><span><span><span>−12</span>−12</span>−<span>12x</span></span>+6</span><span>=<span><span><span><span><span><span>−12</span>+</span>−12</span>+</span>−<span>12x</span></span>+6</span></span>Combine Like Terms:<span>=<span><span><span><span>−12</span>+<span>−12</span></span>+<span>−<span>12x</span></span></span>+6</span></span><span>=<span><span>(<span>−<span>12x</span></span>)</span>+<span>(<span><span><span>−12</span>+<span>−12</span></span>+6</span>)</span></span></span><span>
=<span><span>−<span>12x</span></span>+<span>−<span>18</span></span></span></span>
Answer: Yes, it would be biased. If David asked the question about movies, however, it would not be.
Step-by-step explanation: It would be biased because he is asking listeners to his show who send fan mail. Fan mail is typically only sent by people who enjoy the creator. Therefor, he would be surveying only people who enjoy his podcast so the results would be heavily biased. I am unsure about how the second part of the question relates to the first part. If David were to ask the same 100 individuals about their favorite movies rather than whether or not they liked his podcast, it would not contain biased results because he or his podcast does not have anything to do with movies. :)
Answer:
The standard deviation of weight for this species of cockroaches is 4.62.
Step-by-step explanation:
Given : A different species of cockroach has weights that are approximately Normally distributed with a mean of 50 grams. After measuring the weights of many of these cockroaches, a lab assistant reports that 14% of the cockroaches weigh more than 55 grams.
To find : What is the approximate standard deviation of weight for this species of cockroaches?
Solution :
We have given,
Mean 
The sample mean x=55
A lab assistant reports that 14% of the cockroaches weigh more than 55 grams.
i.e. P(X>55)=14%=0.14
The total probability needs to sum up to 1,
The z-score value of 0.86 using z-score table is z=1.08.
Applying z-score formula,
Where, 
is standard deviation
Substitute the values,
The standard deviation of weight for this species of cockroaches is 4.62.
