Which of these are expressions?
Check all that are true.
a/9
2 + 5
7
8 × 9 - 5 = 72 - 5
0 + 0
Answer:
a/9
2+5
0+0
maybe 7
an expression is any problem that does NOT have an equal sign
Answer:=7
Step-by-step explanation:
2+5
0+0
maybe 7
an expression is any problem that does NOT have an equal sign
NEED HELP I SUCK AT GEOMETRY (OFFERING 100POINTS)!!! best answer get brainlest
Find the measure of angle C
show work and explain!
Answer:
Angle C = 45°
Step-by-step explanation:
Hello There!
If you didn't know opposite angles are congruent in parallelograms
So ∠A≅∠C and ∠B≅∠D
So if ∠A = 45° then ∠C also equals 45°
As it is a parallelogram
[tex]\\ \sf\longmapsto <B\cong <D[/tex]
[tex]\\ \sf\longmapsto <A\cong <C[/tex]
<A=45°[/tex][tex]\\ \sf\longmapsto <C=<A=45°[/tex]
Assume that the helium porosity (in percentage) of coal samples taken from any particular seam is normally distributed with true standard deviation 0.78.
(a) Compute a 95% CI for the true average porosity of a certain seam if the average porosity for 15 specimens from the seam was 4.85. (Round your answers to two decimal places.)
(b) Compute a 98% CI for true average porosity of another seam based on 11 specimens with a sample average porosity of 4.56. (Round your answers to two decimal places.)
(c) How large a sample size is necessary if the width of the 95% interval is to be 0.46? (Round your answer up to the nearest whole number.)
(d) What sample size is necessary to estimate true average porosity to within 0.18 with 99% confidence? (Round your answer up to the nearest whole number.)
Answer:
a) The 95% CI for the true average porosity of a certain seam if the average porosity for 15 specimens from the seam was 4.85 is (4.46, 5.24).
b) The 98% CI for true average porosity of another seam based on 11 specimens with a sample average porosity of 4.56 is (4.01, 5.11).
c) A sample size of 12 is needed.
d) A sample size of 125 is needed.
Step-by-step explanation:
(a) Compute a 95% CI for the true average porosity of a certain seam if the average porosity for 15 specimens from the seam was 4.85.
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
[tex]M = 1.96\frac{0.78}{\sqrt{15}} = 0.39[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is 4.85 - 0.39 = 4.46
The upper end of the interval is the sample mean added to M. So it is 4.85 + 0.39 = 5.24
The 95% CI for the true average porosity of a certain seam if the average porosity for 15 specimens from the seam was 4.85 is (4.46, 5.24).
(b) Compute a 98% CI for true average porosity of another seam based on 11 specimens with a sample average porosity of 4.56. (Round your answers to two decimal places.)
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.98}{2} = 0.01[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.01 = 0.99[/tex], so Z = 2.327.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
[tex]M = 2.327\frac{0.78}{\sqrt{11}} = 0.55[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is 4.56 - 0.55 = 4.01
The upper end of the interval is the sample mean added to M. So it is 4.56 + 0.55 = 5.11
The 98% CI for true average porosity of another seam based on 11 specimens with a sample average porosity of 4.56 is (4.01, 5.11).
(c) How large a sample size is necessary if the width of the 95% interval is to be 0.46?
95% CI means that [tex]z = 1.96[/tex]
A sample of n is needed, and n is found when M = 0.46. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]0.46 = 1.96\frac{0.78}{\sqrt{n}}[/tex]
[tex]0.46\sqrt{n} = 1.96*0.78[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96*0.78}{0.46})^2[/tex]
[tex]n = 11.05[/tex]
Rounding up
A sample size of 12 is needed.
(d) What sample size is necessary to estimate true average porosity to within 0.18 with 99% confidence?
99% CI means that [tex]z = 2.575[/tex]
A sample of n is needed, and n is found when M = 0.18. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]0.18 = 2.575\frac{0.78}{\sqrt{n}}[/tex]
[tex]0.18\sqrt{n} = 2.575*0.78[/tex]
[tex](\sqrt{n})^2 = (\frac{2.575*0.78}{0.18})^2[/tex]
[tex]n = 124.5[/tex]
Rounding up
A sample size of 125 is needed.
A state university locks in costs for a student once a student starts attending the university. The total cost is $23,500. A student has
the following help in covering the costs of school.
• An academic scholarship of $8,200.
• Other scholarships and grants of $7.400.
Grandparents pay $1,000
.
What is the amount that the student will need to save every month in order to pay off the remaining costs in 10 months ?
$690
S820
S1 660
$2 350
Answer:
720
Step-by-step explanation:
24500 (total) subtracted by (10,700 + 5000 + 1600) =7200. 7200 divide by 10 mo=720
If the student will need to save every month in order to pay off the remaining costs in 10 months, the amount she will need to save per month is $690
Amount and interestGiven the following information from the question
The total cost of fee = $23,500
Amount got as help;
An academic scholarship of $8,200.
Other scholarships and grants of $7.400.
Grandparents pay $1,000
Amunt she had = 8200 + 7400 + 1000
Amount she had = $16600
Amount remaining = 23500 - 16600
Amount remaining = $6900
If the student will need to save every month in order to pay off the remaining costs in 10 months, the amount she will need to save per month is $690
Learn more on the amount here:
https://brainly.com/question/25109150
Covert 2/3 years to months
Answer:
7.9 or if you need to round it,it will be 8
Step-by-step explanation:
dont have a explanation nut i hopes this help.
3. Mateus recebe a visita do seu avô Pedro a cada 15 dias. João, o tio dele, o visita a cada 100
e, devido a escalas de trabalho, a cada 12 dias Mateus vai à praia com seus pais. Um belo dia Mans
recebeu a visita do seu avô, do seu tio e foi à praia com seus pais (com o avô e o tio que o visitavam nese
dia). Quantos dias depois este acontecimento se repetirà?
Answer:
Este acontecimento se repetirá 300 dias depois.
Step-by-step explanation:
Quando os eventos se repetirão no mesmo dia?
Cada evento tem uma frequência.
Eles ocorrem simultaneamente a cada x dias, e x é dado pelo MMC(Mínimo Múltiplico Comum) entre as frequência.
Neste problema:
A cada 15 dias o avô visita.
A cada 100 dias o tio visita.
A cada 12 dias vai à praia.
Quantos dias depois este acontecimento se repetirá?
Os três no mesmo dia vão se repetir após x dias, em que x é dado pelo MMC de 15, 100 e 12
MMC de 15, 100 e 12
Fatorando simultâneamente estes valores:
15 - 100 - 12|2
15 - 50 - 6|2
15 - 25 - 3|3
5 - 25 - 1|5
1 - 5 - 1|5
1 - 1 - 1
Então:
mmc(15,100,12) = 2*2*3*5*5 = 300
Este acontecimento se repetirá 300 dias depois.
Will the product of 22.65 x 0.999 be greater than or less than 22.65? Without calculating, explain how you know.
It will be less since as common knowledge, it's a decimal so it'll be a little bit less
I need help on this..... FAST. Think you can help me?
Answer:
.si sey el senocar 18
Step-by-step explanation:.basflone ne ombla
B:
The usual monthly expenses of midas family is 3500.00 for their electric and and with bill, 10,
000 for house and 5,000.00 for their food. The rest of their income will be their savings How much
will be their savings if the couple both earn 10,000.00each
Answer:
$1,500
Step-by-step explanation:
Income - Expenses = Savings
Income = 2 × 10,000 = $20,000
Expenses = 3,500 + 10,000 + 5,000 = $18,500
$20,000 - $18,500 = $1,500 left for Savings
Can you please help I am getting graded:) show work too please
Answer: A - 33/100
Step-by-step explanation:
You have to multiply the first fraction by 10 to make 100 the least common denominator - 3/10(10) = 30/100
Add 30/100+3/100 = 33/100
What is the slope of a line that is perpendicular to the line y = 1/6+ 4
+4?
Answer:
y = 6x + 8?
Step-by-step explanation:
The starting equation was unclear but if its perpindecular, flip the given slope. For example, if the slope was 3/4, its perpindecular slope would be 4/3.
Helppppp meeeee!!!!!!!!!!!
Answer and Step-by-step explanation:
When it says (f + g)(x), it means that it wants you to add the functions together.
So, let's add them.
[tex](2x^2 + 6x - 4) + (5x^3 -6x^2-3)\\\\\\5x^3 - 4x^2 + 6x - 7\\\\\\\\\\\\\\5x^3 - 4x^2 + 6x - 7[/tex]is the answer. (Answer choice B.)
#teamtrees #PAW (Plant And Water)
I WILL GIVE MAX POINTS IF YOU WRITE STEPS AND SOLVE PLZZZZZZ
Answer:
Step-by-step explanation:
so we need two even intergeters that add to 70 when we multiply the bigger by 2 and add the smaller to that soooo
70= 2*y + x
but we can express x in terms of y b/c it's a consecutive even integer soo
(b/c x+2 = y, then x = y -2)
70= 2*y + (y-2)
70 = 2y + y - 2
72 = 3y
24 = y :) nice the bigger is 24 so the smaller is 22
70 = 2*24 + 22
70 = 48 + 22
70 = 70 nice !
bigger = 24
smaller = 22
:)
Answer:
bigger = 24
smaller = 22
Step-by-step explanation:
A holiday store is having a sale on bows and rolls of wrapping paper. One sign in the store states, “Buy 1 bow and 1 roll of wrapping paper for only $6.00.” A second sign in the store states, “5 bows and 1 roll of wrapping paper will only cost $10.00.”
In dollars and cents, the cost of a single roll of wrapping paper costs $
.
Answer:
3.00
Step-by-step explanation:
One bow and and 1 roll of wrapping paper cost 6.00$
so the roll by itself would cost 6.00$
struggle helpppppppp
Answer:
49
Step-by-step explanation:
|-7|=7, and 7*7 = 49
In ΔMNO, the measure of ∠O=90°, the measure of ∠N=38°, and OM = 87 feet. Find the length of NO to the nearest tenth of a foot.
Answer:
111.4
Step-by-step explanation:
trust
How many distinct variables does the expression below
contain?
2x^5+xy^4-zx
Which regular polygon would have each of its interior angles measure 140°?
octagon
nonagon
decagon
heptagon
9514 1404 393
Answer:
nonagon
Step-by-step explanation:
The adjacent exterior angle is 180° -140° = 40°. There are 360°/40° = 9 of those angles around the regular polygon, so it is 9-sided.
The polygon is a nonagon.
Answer:
nonagon
Step-by-step explanation:
i got 100%
Scott is saving coins in a jar. Last week, the jar was 1/4 full. This week, he added more coins, and the jar is now 1/2 full. How much of the jar did Scott fill this week?
Answer:
Scott filled (1/2 - 1/4) of the jar, or 1/4 of the jar this week.
Let me know if this helps!
Answer:
He filled his jar 1/4 more this week.
Step-by-step explanation:
The explanation is very simple, you know that he added 1/4 coins last week and this week he added more coins that filled the jar half way:
1/2 - 1/4 = 1/4
or you can also use:
1/4 + 1/4 = 1/2
Cellulon, a manufacturer of home insulation, wants to develop guidelines for builders and consumers on how the thickness of the insulation in the attic of a home and the outdoor temperature affect natural gas consumption. In the laboratory, it varied the insulation thickness and temperature. A few of the findings are:
Monthly Natural Gas Consumption (cubic feet), Thickness of Insulation (inches), Outdoor Temperature (ºF),
y x1 x2
30.3 6.0 32.0
25.2 12 40
30.5 8 49
On the basis of the sample results, the regression equation is:
yˆ y^ = 57.25 − 1.07x1 − 0.64x2
According to the regression equation, the predicted Monthly Natural Gas Consumption (ŷ) can be estimated by subtracting 1.07 times the Thickness of Insulation (x1) and 0.64 times the Outdoor Temperature (x2) from 57.25.
The regression equation provided is:
ŷ = 57.25 - 1.07x1 - 0.64x2
Where:
ŷ represents the predicted value of Monthly Natural Gas Consumption (cubic feet)
x1 represents the Thickness of Insulation (inches)
x2 represents the Outdoor Temperature (ºF)
Based on the regression equation, the coefficients indicate the relationship between the independent variables (Thickness of Insulation and Outdoor Temperature) and the dependent variable (Monthly Natural Gas Consumption).
The coefficient for x1 (Thickness of Insulation) is -1.07. This means that, holding the Outdoor Temperature constant, for every 1-inch increase in the Thickness of Insulation, the predicted Monthly Natural Gas Consumption is expected to decrease by 1.07 cubic feet.
The coefficient for x2 (Outdoor Temperature) is -0.64. This means that, holding the Thickness of Insulation constant, for every 1-degree Fahrenheit increase in the Outdoor Temperature, the predicted Monthly Natural Gas Consumption is expected to decrease by 0.64 cubic feet.
The constant term in the equation is 57.25. This represents the predicted Monthly Natural Gas Consumption when both the Thickness of Insulation and Outdoor Temperature are zero.
for such more question on regression equation
https://brainly.com/question/22077082
#SPJ8
Need help with this question please !!!
Answer: 27
Step-by-step explanation:
0.8 as a fraction??
You can give your answer
Answer: 4/5
Step-by-step explanation:
0.8 = 8/10 = 4/5
Answer:
4/5
Step-by-step explanation:
Please send help. I really need this asap
Answer:
Part a) The area of the figure is [tex]\frac{9}{2} (4+\pi ) cm^{2}[/tex]
Part b) The perimeter of the figure is [tex]3(2+2\sqrt{2} +\pi )cm[/tex]
Please answer right! Thank you I will give brainalist
Answer:
C [tex]\leq 34[/tex]
Step-by-step explanation:
Answer:
34is the answer gor the question
Simplify the following expression
6y + 8 - 2y + 5y - 9
Answer: 9y-1
:))))))))))))))))))))
How do you get infinitely many solution?
Answer: I’m
Step-by-step explanation: I’d not knkw
Fill in the blank so that the ordered pair is a solution of y = 6x +7: 4,25)
a) 13
b) 1
c) 18
d) 3
Answer:
it is either A OR B
Step-by-step explanation:
Are the sets equivalent?
2) A = {17, 19, 21, 23, 25)
16.
B = {18, 20, 22, 24, 26}
Answer:
Step-by-step explanation:
number of elements in set A=5
number of elements in set B=5
so they are equivalent.
Find the radius or diameter of the circle with the given dimentions.
r = 21 ft
Answer Choices:
a. 50 ft
b. 42 ft
c. 131.9 ft
d. 10.5 ft
Answer:
b. 42
Step-by-step explanation:
Your trying to find the diameter since radius is r
diameter is always double of radius
Brainliest will be given ASAP question below!
Answer:
3/32
Step-by-step explanation:
9/16 × 3/4=27/144=3/16×1/2=3/32