Step-by-step explanation:
d = z - 9
d = 10 - 9 ----> substitute
d = 1
The angles in a triangle are represented by x, x+10, and x+50. What is the measure of the largest angle?
A.70 degrees
B.80 degrees
C.100 degrees
D.90 degrees
Given that,
The angles in a triangle are represented by x, x+10, and x+50.
We had to,
find the measure of the largest angle.
Let's start to solve,
→ x + (x+10) + (x+50) = 180°
→ x + x + x = 180° (-50 -10)
→ 3x = 180° -60
→ 3x = 120
→ x = 120/3
→ x = 40°
Then the value of x + 10,
→ x + 10
→ 40 + 10
→ 50°
Then the value of x + 50,
→ x + 50
→ 40 + 50
→ 90°
The measure of the largest angle is,
→ D. 90 degrees
Hence, option (D) is correct answer.
Step-by-step explanation:
good of you and good workings
The number of calls received by an office on Monday morning between 8:00 AM and 9:00 AM has a mean of 5. Calculate the probability of getting at least 4 calls between eight and nine in the morning.
Answer:
0.735 = 73.5% probability of getting at least 4 calls between eight and nine in the morning.
Step-by-step explanation:
We have the mean during a time interval, which means that the Poisson distribution is used to solve this question.
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
In which
x is the number of sucesses
e = 2.71828 is the Euler number
[tex]\mu[/tex] is the mean in the given interval.
The number of calls received by an office on Monday morning between 8:00 AM and 9:00 AM has a mean of 5.
This means that [tex]\mu = 5[/tex]
Calculate the probability of getting at least 4 calls between eight and nine in the morning.
This is:
[tex]P(X \geq 4) = 1 - P(X < 4)[/tex]
In which
[tex]P(X < 4) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3)[/tex]
So
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
[tex]P(X = 0) = \frac{e^{-5}*5^{0}}{(0)!} = 0.0067[/tex]
[tex]P(X = 1) = \frac{e^{-5}*5^{1}}{(1)!} = 0.0337[/tex]
[tex]P(X = 2) = \frac{e^{-5}*5^{2}}{(2)!} = 0.0842[/tex]
[tex]P(X = 3) = \frac{e^{-5}*5^{3}}{(3)!} = 0.1404[/tex]
Then
[tex]P(X < 4) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) = 0.0067 + 0.0337 + 0.0842 + 0.1404 = 0.265[/tex]
[tex]P(X \geq 4) = 1 - P(X < 4) = 1 - 0.265 = 0.735[/tex]
0.735 = 73.5% probability of getting at least 4 calls between eight and nine in the morning.
Answer by any chance?❤️
Step-by-step explanation:
Question 2.[tex] \frac{ \frac{6}{7} }{ \frac{9}{14} } [/tex]
[tex] = \frac{6}{7} \times \frac{14}{9} [/tex]
[tex] = \frac{2}{1} \times \frac{2}{3} [/tex]
[tex] = \frac{4}{3} = 1 \frac{1}{3} (Ans) [/tex]
Question 3.[tex] \frac{18}{x} = \frac{6}{10} [/tex]
[By cross multiplication]
=> 18 × 10 = 6 × x
[tex] = > \frac{18 \times 10}{6} = x[/tex]
=> 3 × 10 = x
=> x = 30 (Ans)
Which of the following phrases should not be expressed using a negative number?
Answer:
its 1900 Bc. Because BC stand for before chirst
Step-by-step explanation:
Certify Completion Icon Tries remaining:2 A town recently dismissed 10 employees in order to meet their new budget reductions. The town had 7 employees over 50 years of age and 18 under 50. If the dismissed employees were selected at random, what is the probability that exactly 5 employees were over 50
Answer:
0.055 = 5.5% probability that exactly 5 employees were over 50.
Step-by-step explanation:
The employees are removed from the sample without replacement, which means that the hypergeometric distribution is used to solve this question.
Hypergeometric distribution:
The probability of x successes is given by the following formula:
[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}[/tex]
In which:
x is the number of successes.
N is the size of the population.
n is the size of the sample.
k is the total number of desired outcomes.
Combinations formula:
[tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
In this question:
7 + 18 = 25 employees, which means that [tex]N = 25[/tex]
7 over 50, which means that [tex]k = 7[/tex]
10 dismissed, which means that [tex]n = 10[/tex]
What is the probability that exactly 5 employees were over 50?
This is P(X = 5). So
[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}[/tex]
[tex]P(X = 5) = h(5,25,10,7) = \frac{C_{7,5}*C_{18,5}}{C_{25,10}} = 0.055[/tex]
0.055 = 5.5% probability that exactly 5 employees were over 50.
x=cos(2t), y=sin(2t) find a rectangular coordinate equation for the curve by eliminating the parameter
Answer:
x^2+y^2=1
Step-by-step explanation:
Since cos^2(x)+sin^2(x)=1, x^2+y^2=1
Which graph shows data that would allow the most accurate prediction for the number of water bottles a vendor sells based on the daily high temperature?
Graph A
Daily High Temperatures and Bottled Water Sales
On a graph, points are scattered all over the graph.
Graph B
Daily High Temperatures and Bottled Water Sales
On a graph, points are scattered all over the graph.
Graph C
Daily High Temperatures and Bottled Water Sales
On a graph, points are grouped together and form a line with positive slope.
Graph D
Daily High Temperatures and Bottled Water Sales
On a graph, points are grouped together and increase.
PLS HELP ILL GIVE BRAINLIEST FAST
9514 1404 393
Answer:
Graph C: Daily High Temperatures and Bottled Water Sales
On a graph, points are grouped together and form a line with positive slope.
Step-by-step explanation:
Apparently, Graph C shows data with the greatest degree of correlation. This suggests that any model of the data is likely to have less error than if the data were less well correlated.
Answer:
Graph C: Daily High Temperatures and Bottled Water Sales
On a graph, points are grouped together and form a line with positive slope.
Step-by-step explanation:
pleaseee i need help!
2 questions in one pleasee 90 points!
Answer:
A the answer is A if you look at it .
Answer:
The first one is B) point D
The second one is D) (0,0)
Hope this helps!
btw, coordinates are in (x,y) form, so the other answer above me is wrong.
Please help, I’m not sure about this question.
How many millitiers are in 4.55 liters?
Answer:
v nnv vb n
Step-by-step explanation:
b ng chfxhc.jx.gc,fhxfgfdkhgvn gghcjfuoctykfd mmyegfiuegfypgerukf khergfuoegrfyurgfirge jgreuyofrgiregvoifgr riygfepiygfreu;k frugfyrfbhrevf rrgfbreuobghfre rgeuherhbgerui freurehuregh ruogysfhurgiugwhlerghre rgiuyrge97grukbgr ker ruipuhrgeugregariyarga ;rskfglfsglgsfuifgryrgljs kjger;ugiergs hope this was helpful good luck!
Denver's elevation is 5280 feet above sea level. Death Valley is -282 feet. Is Death Valley located above sea level or below sea level???
(plz answer, due date is semtemper)
9514 1404 393
Answer:
below
Step-by-step explanation:
When signed numbers are used to represent elevation with respect to sea level, positive signs are used for values above sea level, and negative signs are used for values below sea level. The given elevation of Death Valley indicates it is 282 feet below sea level.
Please help , write your answer I will be giving 10 points
Answer:
yes it represents the graph accurately
the sum of five consecutive number is 45
Answer:
7, 8, 9, 10, 11
Step-by-step explanation:
7+8+9+10+11
7 + 8 = 15
15 + 9 = 24
24 + 10 = 34
34 + 11 = 45
Find an equation of the line that is the perpendicular bisector of the line segment joining the points (6,2) and (18,6)
Answer:
y= -3x +40
Step-by-step explanation:
Properties of perpendicular bisector:
• perpendicular to the given line
• cuts through the center of the given line
The equation of a line can be written in the form of y=mx +c, where m is the gradient and c is the y -intercept.
Let's find the gradient of the given line first.
[tex]\boxed{gradient = \frac{y1 - y2}{x1 - x2} }[/tex]
Gradient of given line
[tex] = \frac{6 - 2}{18 - 6} [/tex]
[tex] = \frac{4}{12} [/tex]
[tex] = \frac{1}{3} [/tex]
The product of the gradients of perpendicular lines is -1.
m(⅓)= -1
m= -1(3)
m= -3
Substitute m= -3 into the equation:
y= -3x +c
To find the value of c, substitute a pair of coordinates in which the perpendicular bisector passes through into the equation. Since perpendicular bisectors passes through the center of the segment, we can find the point in which the perpendicular bisector passes through using the mid- point formula.
[tex]\boxed{midpoint = ( \frac{x1 + x2}{2} , \frac{y1 + y2}{2} )}[/tex]
Midpoint
[tex] = ( \frac{6 + 18}{2} , \frac{6 + 2}{2} )[/tex]
[tex] = ( \frac{24}{2} , \frac{8}{2} )[/tex]
[tex] = (12,4)[/tex]
y= -3x +c
when x= 12, y= 4,
4= -3(12) +c
4= -36 +c
c= 4 +36
c= 40
Thus, the equation of the perpendicular bisector is y= -3x +40.
6/5 times 17/18 in lowest terms
Answer:
17/15
Step-by-step explanation:
6/5 * 17/18
1/5 * 17/3
17/15
degree and classification of 4x^2+32x+63?
nvm its quadratic trinomial
Answer:
Pertaining to the mathematical expression conveyed, the answer to such proposed interrogate is acknowledged as the following:
Degree: 2nd degree term.
Classification: Quadratic trionomial.
Step-by-step explanation:
Evaluating the Degree:
The degree is acknowledged as the predominating term adjacent to a base of a peculiar value that denotes the particular allocation within a polynomial.
4x^2 has the highest degree of 2.
32x has the degree of one, being that x individually is x^1.
Since polynomials are defined by the term in which obtains the greatest degree, ^2 is referred to as quadratic, whereas ^3 is cubic, ^4…
Classification Evaluation:
Such could be determined by evaluating for the quantity of terms present within the mathematical expression or statement.
4x^2 is the first term.
32x is the second term.
63 is the third term (considered a constant).
Thus, the correct answer is a quadratic trinomial.
*I hope this helps.
Write an equation of the line through each pair of points in slope-intercept form.
a(– 3,–2) and (–3,4)
b(3,2)and (–4,–5)
Answer and I will give you brainiliest
Answer:
see below
Step-by-step explanation:
a) (– 3, –2) and (–3, 4)
First you want to find the slope of the line that passes through these points. To find the slope of the line, we use the slope formula: (y₂ - y₁) / (x₂ - x₁)
Plug in these values:
(4 - (-2) / (-3 - (-3))
Simplify the parentheses.
= (4 + 2) / (-3 + 3)
Simplify the fraction.
(6) / (0)
= undefined
If your slope is undefined, it is a vertical line. The equation of a vertical line is x = #.
In this case, the x-coordinate for both points is -3.
Therefore, your equation is x = -3.
b) (3, 2) and (–4, –5)
First you want to find the slope of the line that passes through these points. To find the slope of the line, we use the slope formula: (y₂ - y₁) / (x₂ - x₁)
Plug in these values:
(-5 - 2) / (-4 - 3)
Simplify the parentheses.
= (-7) / (-7)
Simplify the fraction.
-7/-7
= 1
This is your slope. Plug this value into the standard slope-intercept equation of y = mx + b.
y = 1x + b or y = x + b
To find b, we want to plug in a value that we know is on this line: in this case, I will use the first point (3, 2). Plug in the x and y values into the x and y of the standard equation.
2 = 1(3) + b
To find b, multiply the slope and the input of x(3)
2 = 3 + b
Now, subtract 3 from both sides to isolate b.
-1 = b
Plug this into your standard equation.
y = x - 1
This is your equation.
Check this by plugging in the other point you have not checked yet (-4, -5).
y = 1x - 1
-5 = 1(-4) - 1
-5 = -4 - 1
-5 = -5
Your equation is correct.
Hope this helps!
The ratio of the side lengths of Rectangle A to Rectangle B is 3 to 7. What is the
ratio of their areas?
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Answer:
9 : 49
Step-by-step explanation:
Assuming the rectangles are similar, the ratio of their areas is the square of the ratio of their side lengths.
sides ratio = 3 : 7
areas ratio = 3² : 7² = 9 : 49
What is the slope of the line that contains these points?
х
-1
0
1
2
y
10
18
26
34
slope:
Answer:
8.
Step-by-step explanation:
The slope =
difference in y coordinates of 2 points / difference in coordinates of corresponding x coordinates.
So taking the first 2 points:
The slope = (18-10) / 0 - (-1)
= 8/1
= 8.
This is confirmed by slope between the second and third points
slope = 26-18/ (1-0) = 8.
My class consists of 8 men and 7 women. I want to pick a group of 6 people for research.
Write each answer using fraction as needed.
a. In how many different ways can I pick this group?
b. What is the probability of having exactly 3 men in the group?
c. What is the probability of all the selected people in group are women?
d. What is the probability of having at least one man in the group?
Answer:
a.5005
b.[tex]\frac{1960}{5005}[/tex]
c.1/715
d.714/715
Step-by-step explanation:
We are given that
Total men=8
Total women=7
Total people, n=8+7=15
r=6
a.
Combination formula:
Selection of r out of n people by total number of ways
[tex]nC_r[/tex]
Using the formula
We have n=15
r=6
Total number of ways=[tex]15C_6[/tex]
Total number of ways=[tex]\frac{15!}{6!9!}[/tex]
Using the formula
[tex]nC_r=\frac{n!}{r!(n-r)!}[/tex]
Total number of ways=[tex]\frac{15\times 14\times 13\times 12\times 11\times 10\times 9!}{6\times 5\times 4\times 3\times 2\times 1\times 9!}[/tex]
Total number of ways=5005
b. The probability of having exactly 3 men in the group
=[tex]\frac{8C_3\times 7C_3}{15C_6}[/tex]
Using the formula
Probability,[tex]P(E)=\frac{favorable\;cases}{Total\;number\;of\;cases}[/tex]
The probability of having exactly 3 men in the group=[tex]\frac{\frac{8!}{3!5!}\times \frac{7!}{3!4!}}{5005}[/tex]
=[tex]\frac{\frac{8\times 7\times 6\times 5!}{3\times 2\times 1\times 5!}\times \frac{ 7\times 6\times 5\times 4!}{3\times 2\times 1\times 4!}}{5005}[/tex]
=[tex]\frac{56\times 35}{5005}[/tex]
The probability of having exactly 3 men in the group
=[tex]\frac{1960}{5005}[/tex]
c. The probability of all the selected people in the group are women
=[tex]\frac{8C_0\times 7C_6}{5005}[/tex]
The probability of all the selected people in the group are women
[tex]=\frac{\frac{8!}{0!8!}\times \frac{7\times 6!}{6!1!}}{5005}[/tex]
The probability of all the selected people in the group are women
[tex]=\frac{7}{5005}=\frac{1}{715}[/tex]
d. The probability of having at least one man in the group
=1- probability of all the selected people in group are women
The probability of having at least one man in the group
[tex]=1-\frac{1}{715}[/tex]
[tex]=\frac{715-1}{715}[/tex]
[tex]=\frac{714}{715}[/tex]
The probability of having at least one man in the group [tex]=\frac{714}{715}[/tex]
A zookeeper perdiceted that the wight of a newborn lion would be 2.8 pounds when the zoo’s lion gave birth ,the newbor. Weight 3.5 pounds what is the zookeeper’s percent error ? Round to nerds err percent
Answer:
20%
Step-by-step explanation:
3.5 - 2.8 = 0.7
0.7 ÷ 3.5 = 0.2
0.2 × 100 = 20
The answer is 20%.
Hope this helped.
Answer:
predicted wight=2.8
Actual wight = 3.5 pounds
(3.5-2.8)/3.5
=0.7/3.5 × 100
=100/5=20%
Answer: 20%
OAmalOHopeO
write the equation of a line of a line passing through the points (3,1) and (6,3).
Answer:
i think its 2 1
Step-by-step explanation:
Answer:
y =2/3x-1
Step-by-step explanation:
First find the slope
m = ( y2-y1)/(x2-x1)
= ( 3-1)/ (6-3)
= 2/3
The slope intercept form of a line is
y = mx+b where m is the slope and b is the y intercept
y = 2/3x +b
Using a point
3 = 2/3(6)+b
3 = 4+b
3-4 =b
-1=b
y =2/3x-1
In a certain town, 22% of voters favor the construction of a new hospital. For groups of 21 voters, find the variance for the number who did not favor the new hospital.
a. 1.9 voters
b. 4.6 voters
c. none of the given answers is correct
d. 3.6 voters
e. 13 voters
Answer:
Variance = 3.6 voteres
Step-by-step explanation:
Probability of favour voters, P = 0.22
Total number of voters, n = 21
The probability of voters who are in not favour of new hospital construction = 1 - P
The probability of voters who are in not favour of new hospital construction = 1 - 0.22
The probability of voters who are in not favour of new hospital construction, P* = 0.78
Variance = n x p* x (1 - p*)
Variance = 21 x 0.78 x 0.22
Variance = 3.6 voters
help !!!! what’s the solution
1/2 + 4 5/8 please help
Answer:
[tex]5 \frac{1}{8}[/tex]
Step-by-step explanation:
Remember that [tex]\frac{1}{2} = \frac{4}{8}[/tex], so we want to find [tex]\frac{4}{8} + 4 + \frac{5}{8} = 4 + \frac{9}{8}[/tex]. However, this is not in it's simplest form because [tex]\frac{9}{8}[/tex] should be [tex]1 \frac{1}{8}[/tex]. Therefore, the final answer is [tex]4+1+\frac{1}{8} = 5 \frac{1}{8}[/tex].
Answer:
5 1/8 correct answer to question
Question 4 of 10
What else would need to be congruent to show that ABC= AXYZ by SAS?
Answer:
D
Step-by-step explanation:
The correct answer is D. Answered by Gauthmath
⅗ Write the numerator and denominator of each of the following rational numbers
Answer:
1 3 5 7 9 11
Step-by-step explanation:
same like this do the question the answer will come
Match each shape to the number of lines of reflection that will reflect the shape onto itself. Drag the items on the left to the correct location on the right.
Answer:
rectangle- 2 lines of reflection
trapezoid- 0 lines of reflection
regular pentagon- 5 lines of reflection
square- 4 lines of reflection
Step-by-step explanation:
What is y-3=3/4(x-5) in standard form?
Answer:
[tex]y-3=\frac{3}{4} (x-5)\\\\y-3=\frac{3}{4}x-\frac{3}{4}(5)\\\\y=\frac{3}{4} x+3-\frac{15}{4} \\\\y=\frac{3}{4} x+\frac{12}{4} -\frac{15}{4} \\\\y=\frac{3}{4} x-\frac{3}{4}[/tex]
Is this standard form? :\
Answer:
3x-4y=3
Step-by-step explanation:
Hi there!
We are given the equation y-3=[tex]\frac{3}{4}(x-5)[/tex], and we want to write it in standard form
Standard form is given as ax+by=c, where a, b, and c are integer coefficients, a CANNOT be 0 and CANNOT be negative, and b also CANNOT be 0
So let's expand the parentheses in the equation
Do the distributive property
y-3=[tex]\frac{3}{4}x-\frac{15}{4}[/tex]
Add 3 to both sides
y=[tex]\frac{3}{4}x-\frac{3}{4}[/tex]
We expanded the parentheses, but the equation is now in slope-intercept form (y=mx+b, where m is the slope and b is the y intercept)
Remember that we want it in standard form, which is ax+by=c
Subtract [tex]\frac{3}{4}x[/tex] from both sides
[tex]\frac{-3}{4}x+y=\frac{-3}{4}[/tex]
Remember that the coefficients of a, b, and c need to be integers, and also that a (the coefficient in front of x) CANNOT be negative
So multiply both sides by -4
[tex]-4(\frac{-3}{4}x+y)=-4(\frac{-3}{4})[/tex]
Distribute -4 to every number
[tex]-4(\frac{-3}{4}x)+-4(y)=-4(\frac{-3}{4})[/tex]
Multiply
[tex]\frac{12}{4}x-4y=\frac{12}{4}[/tex]
Simplify
3x-4y=3
There's the equation in standard form
Hope this helps!
The mean monthly rent for a one-bedroom apartment without a doorman in Manhattan is 2630. Assume the standard deviation is$500 . A real estate firm samples 100 apartments. Use the TI-84 Plus calculator.a) What is the probability that the sample mean rent is greater than $27007?b) What is the probability that the sample mean rent is between $2450 and $2550? c) Find the 25th percentile of the sample mean. d) Would it be unusual if the sample mean were greater than $26457?e) Do you think it would be unusual for an individual to have a rent greater than $2645? Explain. Assume the variable is normally distributed.
Answer:
a) 0.0808 = 8.08% probability that the sample mean rent is greater than $2700.
b) 0.0546 = 5.46% probability that the sample mean rent is between $2450 and $2550.
c) The 25th percentile of the sample mean is of $2596.
d) |Z| = 0.3 < 2, which means it would not be unusual if the sample mean was greater than $2645.
e) |Z| = 0.3 < 2, which means it would not be unusual if the sample mean was greater than $2645.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
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 p-value, we get the probability that the value of the measure is greater than X.
If |Z|>2, the measure X is considered unusual.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
The mean monthly rent for a one-bedroom apartment without a doorman in Manhattan is $2630. Assume the standard deviation is $500.
This means that [tex]\mu = 2630, \sigma = 500[/tex]
Sample of 100:
This means that [tex]n = 100, s = \frac{500}{\sqrt{100}} = 50[/tex]
a) What is the probability that the sample mean rent is greater than $2700?
This is the 1 subtracted by the p-value of Z when X = 2700. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{2700 - 2630}{50}[/tex]
[tex]Z = 1.4[/tex]
[tex]Z = 1.4[/tex] has a p-value 0.9192
1 - 0.9192 = 0.0808
0.0808 = 8.08% probability that the sample mean rent is greater than $2700.
b) What is the probability that the sample mean rent is between $2450 and $2550?
This is the p-value of Z when X = 2550 subtracted by the p-value of Z when X = 2450.
X = 2550
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{2550 - 2630}{50}[/tex]
[tex]Z = -1.6[/tex]
[tex]Z = -1.6[/tex] has a p-value 0.0548
X = 2450
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{2450 - 2630}{50}[/tex]
[tex]Z = -3.6[/tex]
[tex]Z = -3.6[/tex] has a p-value 0.0002
0.0548 - 0.0002 = 0.0546.
0.0546 = 5.46% probability that the sample mean rent is between $2450 and $2550.
c) Find the 25th percentile of the sample mean.
This is X when Z has a p-value of 0.25, so X when Z = -0.675.
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]-0.675 = \frac{X - 2630}{50}[/tex]
[tex]X - 2630 = -0.675*50[/tex]
[tex]X = 2596[/tex]
The 25th percentile of the sample mean is of $2596.
Question d and e)
We have to find the z-score when X = 2645.
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{2645 - 2630}{50}[/tex]
[tex]Z = 0.3[/tex]
|Z| = 0.3 < 2, which means it would not be unusual if the sample mean was greater than $2645.
