Answer:
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".
Let X the random variable that represent the Shear strength of a population, and for this case we know the distribution for X is given by:
Where and
And let represent the sample mean, the distribution for the sample mean is given by:
On this case
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 on this way:
And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.
Answer:
V(t)=5000( 9/10
)^t
Step-by-step explanation:
ANSWER
EXPLANATION
We want expand:
We expand using the distributive to obtain:
Simplify further by combining the two terms in the middle:
Answer:
2) 62.5 wpm
3) 12.7 miles per gallon
4)18 commercials per hour
5) 22.9 ounces per dollar
Step-by-step explanation:
2) 500 words / 8 minutes = 62.5 words per 1 minute
3) 216 miles / 17 gallons = 12.7 miles per gallon
4) 36 commercials / 2 hours = 18 commercials per hour
5) 64 oz / $2.79 = 22.9 oz per $1