Answer:
The value of ROE that will be exceeded by 78% of the firms is -1.77%.
Step-by-step explanation:
Problems of normally distributed samples can be 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:
The mean ROE for the firms studied was 14.93% and the standard deviation was 21.74%. This means that 
What value of ROE will be exceeded by 78% of the firms?
This is the value of X when Z has a pvalue of 1-0.78 = 0.22.
This is 
So:




The value of ROE that will be exceeded by 78% of the firms is -1.77%.
Answer:
Fast ball challenge
Step-by-step explanation:
Given
Slow Ball Challenge




Fast Ball Challenge




Required
Which should he choose?
To do this, we simply calculate the expected earnings of both.
Considering the slow ball challenge
First, we calculate the binomial probability that he hits all 7 pitches

Where
--- pitches
--- all hits
--- probability of hit
So, we have:




Using a calculator:
--- This is the probability that he wins
i.e.

The probability that he lose is:
---- Complement rule


The expected value is then calculated as:


Using a calculator, we have:
Considering the fast ball challenge
First, we calculate the binomial probability that he hits all 3 pitches

Where
--- pitches
--- all hits
--- probability of hit
So, we have:



Using a calculator:
--- This is the probability that he wins
i.e.

The probability that he lose is:
---- Complement rule


The expected value is then calculated as:


Using a calculator, we have:

So, we have:
-- Slow ball
--- Fast ball
<em>The expected earnings of the fast ball challenge is greater than that of the slow ball. Hence, he should choose the fast ball challenge.</em>
The way to solve is using order of operation PEMDAS. Its very easy. You should be able to solve it yourself. I'll give you the first 3 answers:
1. g/6=x
2. x=1/2u+1
3. z-m=x
I would give you all the answers but it would be best if you did it yourself. You teacher and parents would be much happier if you learnt the skill. Hope this answer helps! Mark as brainliest! :)
Area of trapezium= 1/2 × (a+b) × h
= 1/2 × (12 + 8) × 8
= 1/2 × 20 × 8
= 10 × 8
= 80 cm^3
Hope it helps you
Answer:
Hence the area of CD bought by Nathan is <em>22.2784 square inches.</em>
Step-by-step explanation:
The length and width of a CD bought by Nathan is
inches.
As CD have the same length and width this means it will be of the shape of a square.
Hence, the area of CD is given by:
Area of CD=length×width
= 
=
=
=
=
Hence the area of CD bought by Nathan is 22.2784 square inches.