First one, cause it is to dramatic!!!!!!!!!!!!!!!
hope this helps, may I have brainliest?
Answer:
Due to the higher z-score, Jane did better in class.
Step-by-step explanation:
Z-score:
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 question:
Whoever's grade had the better z-score did better in class.
Mary's:
Mean of 85, standard deviation of 5, grade of 88. This means that
. So



Jane's
Mean of 80, standard deviation of 10, grade of 88. This means that
. So



Due to the higher z-score, Jane did better in class.
Answer:
Step-by-step explanation:
There are two steps to this problem. The first step is to make an equation for the cost of each company. The cost of each one involves 2 variables. However, we can ignore the number of days since the question asks for per day.
CostA = 90 + .40(miles)
CostB = 30 + .70(miles)
We want to know when A is a better deal or when A costs less. That is when CostA < CostB. We can then substitute the right sides of our equations into the inequality. This will give:
90 + .40(miles) < 30 + .70(miles) This is where we will now begin to solve for the number of miles.
-30 -30 Subtract 30 from both sides.
60 + .4(miles) < .7(miles) Simplify
-.4(miles) -.4(miles) Subtract .4(miles) from both sides
60 < .3(miles) Simplify
/.3 /.3 Divide both sides by .3
200 < miles Simplify
So for A to cost less the number of miles must be greater than 200.