Answer:
a) 
b) 
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Part a
Let X the random variable that represent the weights of a population, and for this case we know the distribution for X is given by:
Where 
and 
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability like this:
And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.
Part b
For this case we select a sample size of n =32. Since the distribution for X is normal then the distribution for the sample mean 
is given by:
And the new z score would be:
You want to get familiar with what the slope-intercept form equation means. even though the discussion board covers some of this... slope-intercept is y = mx + b, and in it, x and y are a point on your graph (x, y), m is the slope, and b is your y-intercept. in word problems, any constant will typically be b.
but, really, to answer this word problem, you don't have to think so hard about y = mx + b. just read the problem and bring your information together:
"the venue will cost $1500 to rent for an evening"
"$25 per person"
so they only gave you two bits of information, and you just have to decide where they fit. if the venue costs $1500 for an evening, that's a fixed cost--the 1500 isn't going to go up or down depending on the number of people at the charity event. it stays. you're paying 1500 regardless, even if 2 people show up. because the discussion board states that b should represent your starting amount, you're automatically $1500 in the hole, because you have to spend that much to get the venue. you will, however, write it as a positive integer, because the question wants you to calculate the total cost, by my understanding--you're adding the cost of the people with the cost of the venue.
$25 is not a fixed amount. if it's $25 per person, then if 2 people come, it costs $50, if 3 people arrive, it costs $75. this cost is dependent upon the number of people, which you can call "x"
with that information, write any other equation you would for a word problem:
y = 25x + 1500
that's your equation, and it just so happens that this equation is in y = mx + b format. the x-value represents the number of people who show up for the charity; the y-value represents the overall cost.
and you need three solutions for this equation--which, luckily, is a quick and easy process!! choose an x-value and solve for y.
y = 25x + 1500
when x = 1...
y = 25(1) + 1500
y = 25 + 1500
y = 1525
ordered pair: (1, 1525)
when x = 2...
y = 25(2) + 1500
y = 50 + 1500
y = 1550
ordered pair: (2, 1550)
when x = 3...
y = 25(3) + 1500
y = 75 + 1500
y = 1575
ordered pair: (3, 1575)
i hope that helped!!
Answer:
none of these have a solution of 2.
Step-by-step explanation:
4x+ 15 = 27
x=3
x + 6 =3
x = 3
2(x+5)=18
x = 4
x + 9 = 6
x = -3
if my understanding of what the equations are supposed to be please let me know what they are supposed to be, because with the way they are typed it is hard to tell :)
