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.
None is necessarily true.
Even though you have your money in an interest-bearing savings vehicle, its value (purchasing power) may actually decrease if the interest rate is not at least as great as the inflation rate.
In periods of inflation, the value of money decreases over time. In periods of deflation, the value of money increases over time. It tends to be difficult to regulate an economy so the value of money remains constant over time.
The present value of money is greater than the future value in inflationary times. The opposite is true in deflationary times.
_____
In the US in the middle of the last century, inflation rates were consistently 2-3% per year and savings interest rates were perhaps 4-6%. Money saved actually increased in value, and the present value of money was greater than the future value. These days, inflation is perhaps a little lower, but savings interest rates are a lot lower, so savings does not outpace inflation the way it did. The truth or falsity of all these statements depends on where and when you're talking about.
Answer:
5 parts are shaded and 4 parts are white so:
There are 9 parts all together.
We can then form ratio's of the white areas and the shaded areas:
White Area Ratio =
Shaded Area Ratio =
Let the area of sqaure be equated to x, which means let the entire area of the square equal to x:
x = Area of whole square
Now we can form an equation :
So now we just need to solve for x:
The area of the square is: