Question

Results for this submission Entered Answer Preview Result 0.3707 0.3707 incorrect 0.1357 0.1357 incorrect At least one of the answers above is NOT correct. (1 point) The number of pizzas consumed per month by university students is normally distributed with a mean of 8 and a standard deviation of 3 A. What proportion of students consume more than 9 pizzas per month? Probability3707 B. What is the probability that in a random sample of size 11, a total of more than 99 pizzas are consumed? (Hint: What is the mean number of pizzas consumed by the sample of 11 students?) Probability0.1357

Answer 1

ANSWER:

MEAN(u)=8

STANDARD DEVIATION($\sigma$)=3

A)

To find: P(X>9)

Now, Converting

P(X>9)=P($\frac{X-u}{\sigma }$> $\frac{9-u}{\sigma }$ )= P($\frac{X-u}{\sigma }$> $\frac{9-8}{3 }$ )=P(Z>0.33)=1-P(Z<0.33)

Now, According to comulative properties of the standard normal distribution N(0,1)

P(Z<0.33)=0.6293

=1-0.6293

=0.3707

B)

P(X>99/11)=P(X>9)=0.3707(ACCORDING TO PART A SOLVED ABOVE)

Hence,Most probably your second answer is incorrect that's why it shows submission error.