Answer:
15.39% of the scores are less than 450
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
What percentage of the scores are less than 450?
This is the pvalue of Z when X = 450. So
has a pvalue of 0.1539
15.39% of the scores are less than 450
Answer: Option C)1 over 15 minus 1 over x equals 1 over 20
Explanation:
Since, Micah can fill a box with books in 15 minutes.
Therefore, the work done by Micah in one minute= 1/15
Also, Sydney takes the books out puts them on a shelf.
And the times taken by Micah when Sydney is also taking the books outside from the self= 20 minutes
Therefore, the work done by Micah in one minute when Sydney taking books out of the box= 1/20
Let Sydney alone takes x minutes to take books outsides the shelf.
Then, work done by Sydney in one minute=1/x
Thus, the work done by Sydney( by taking books out of the box)= the work done by Micah - work done by Micah and Sydney simultaneously= 1/15-1/20
⇒1/x=1/15-1/20
⇒1/15-1/20=1/x
⇒1/15-1/x=1/20 is the required expression.
Therefore, Option C is correct.
Answer:
m+1
Step-by-step explanation:
1/3(9 - 6m) + 1/4 (12m-8)
Distribute
1/3 *9 - 1/3 *6m + 1/4 * 12m - 1/4 *8
3 -2m + 3m -2
Combine like terms
-2m+3m +3-2
m+1
