The answer is B I think (the picture is a little hard to see)
Answer:
a
Step-by-step explanation:
because I have did this at school
Answer:
And we can find this probability using the complement rule:
And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the scores of a population, and for this case we know the distribution for X is given by:
Where
and
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability using the complement rule:
And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.
First change the mixed fraction into an improper fraction
7 1/2 = 15/2
Next, change multiply 2 to both numerator and denominator
15 x 2 = 30
2 x 2 = 4
30/4
Each piece needs 3/4 of an inch. Divide 30 with 3
30/3 = 10
c) 10 pieces is your answer
hope this helps