Answer:
x=6,y= 7
Step-by-step explanation:
-6x +7y= 13
-6x+8y=20
-y = -7
divide through by -1
y =7
sub y= 7 in equation 1
then x= 6
Answer:
a)
, in which z is related to the confidence level.
b) A sample size of 991 is needed.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
The margin of error is:

In 16% of all homes with a stay-at-home parent, the father is the stay-at-home parent
This means that 
a. What sample size is needed if the research firm's goal is to estimate the current proportion of homes with a stay-at-home parent in which the father is the stay-at-home parent with a margin of error of 0.03 (round up to the next whole number).
This is n for which
. So





, in which z is related to the confidence level.
Question b:
99% confidence level,
So
, z is the value of Z that has a pvalue of
, so
.



Rounding up
A sample size of 991 is needed.
The correct answer is C) -15.
Anyways, I hope you have a wonderful evening :)
Jeremy's height is 67.2 inches
The diagram below represents situation
<h3>Proportion</h3>
Proportion says that two ratios (or fractions) are equal. This a mathematical comparison between numbers.
Therefore, let's establish the proportion in this situation
- Malik height / Malik shadow = Jeremy height / Jeremy shadow
Therefore,
cross multiply
72 × 56 = 60x
60x = 4032
divide both sides by 60
x = 4032 / 60
x = 67.2
Therefore, Jeremy's height is 67.2 inches
learn more on proportion here: brainly.com/question/26258657
Answer:
8quarters 12dimes
Step-by-step explanation: