Answer:
8^-11
Step-by-step explanation:
The applicable rule of exponents is ...
(a^b)(a^c) = a^(b+c)
Then we have ...
(8^(-2))·(8^(-9)) = 8^(-2-9) = 8^-11
Cesium-137 has a half-life of about 30 years. A) Find the annual decay rate and round final result to 4 decimal places. B) Find the continuous decay rate and round final result to 4 decimal places. C) How long will it take for a 10 gram sample to decay to 1 gram? Round to nearest year and interpret your result with a complete sentence. D) Complete this statement: as x goes to infinity, y goes to ___.
Answer:
0.02280.0231100 years0Step-by-step explanation:
The exponential equation for the fraction remaining after x years can be written as ...
y = (1/2)^(x/30)
A) For x=1, the fraction remaining is ...
y = (1/2)^(1/30) ≈ 0.97716 = 1 - 0.0228
Of the original amount, 0.0228 decays each year.
__
B) The continuous decay rate is the natural log of the growth factor, so is ...
ln(0.97716) = -0.0231
The continuous decay rate is 0.0231 of the present amount (per year).
__
C) For y=.10 (1/10 of the original amount) we find x to be ...
.1 = .5^(x/30)
ln(.1) = (x/30)ln(.5) . . . . . take the natural log
30ln(0.1)/ln(0.5) = x ≈ 100 . . . years
It will take 100 years for a 10-gram sample to decay to 1 gram.
__
D) As x goes to infinity, y goes to zero.
_____
The relationship between growth rate and growth factor is ...
growth factor = 1 + growth rate
When the growth rate is negative, it is called a decay rate.
in the factory 25 men working 26 hour can produce 1300 radios . how manny hours must the same group of men work to produce 450 radios
Answer:
9 hours
Step-by-step explanation:
Since the group of men remains the same, number of hours is proportional to number of radios.
1300/26 = 450/h
h = 26 * 450 / 1300 = 9 hours
PLEASE ANSWER ASAP!!!!
Question refers to Table in the picture
Use a proportional reasoning statement like the one in the picture to determine how many feet are in 3 miles. Notice that the conversion fact 1 mile = 5,280 feet is written as a ratio in the picture.
A. x = 15,840 feet
B. x = 10,560 feet
C. x = 21,120 feet
D. x = 26,400 feet
any unrelated answer will be reported
Answer:
The answer is A 15,840, because 5,280 x 3 is equivalent to A
Answer:
A. x = 15,840 feet.
Step-by-step explanation:
[tex]\frac{5280 feet}{1 mile} =\frac{x feet}{3 miles}[/tex]
[tex]\frac{5280}{1} =\frac{x}{3}[/tex]
1 * x = 5,280 * 3
x = 15,840 feet
So, your answer is A. x = 15,840 feet.
Hope this helps!
What is the area of polygon EFGH?
On a map’s coordinate grid, Panthersville is located at (−3, 2), and Heel City is located at (4, 8). Falconton is the midpoint between Panthersville and Heel City. What is the approximate distance from Panthersville to Falconton? (Each unit on the grid represents 1 mile.) A. 3.25 miles B. 4.61 miles C. 5.00 miles D. 9.22 miles
Answer:
B. 4.61 miles
Step-by-step explanation:
midpoint is (-3+4)/2, (2+8)/2 = (1/2, 5)
distance = √(-3-1/2)² + (2 - 5)² = 4.609772299
which of the following greatest
6+(-2)
6-(-2)
6×(-2)
6+(-2)
f(x) = -3x + 7
What is f (0)?
Answer:
f(0) = 7
Step-by-step explanation:
f(x) = -3x + 7
Let x =0
f(0) = -3*0 + 7
f(0) = 7
Question 1 (Multiple Choice Worth 4 points)
(08.01) Looking at the spread of your data best fits which step of the statistical process?
Answer:
The answer is "Analysis the information by chart and number processes".
Step-by-step explanation:
They already have articulated a query and also gathered information unless you are searching only at the distribution of your results. Those who are ready to analyze your results for all are there.
Find the (a) mean, (b) median, (c) mode, and (d) midrange for the data and then (e) answer the given question. Listed below are the weights in pounds of 1111 players randomly selected from the roster of a championship sports team. Are the results likely to be representative of all players in that sport's league?
278 303 186 292 276 205 208 236 278 198 208
a. Find the mean.
The mean is ? pound(s).
(Type an integer or a decimal rounded to one decimal place asneeded.)
b. Find the median.
The median is ? pound(s).
(Type an integer or a decimal rounded to one decimal place asneeded.)
c. Find the mode.
Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
A. The mode(s) is(are) ? pound(s).
(Type an integer or a decimal. Do not round. Use a comma to separate answers as needed.)
B. There is no mode.
d. Find the midrange.
The midrange is ? pound(s).
(Type an integer or a decimal rounded to one decimal place asneeded.)
e. Are the results likely to be representative of all players in that sport's league?
A. The results are not likely to be representative because the median is not equal to the mode.
B. The results are likely to be representative because a championship team is most likely representative of the entire league.
C. The results are not likely to be representative because the median is not equal to the mean.
D. The results are not likely to be representative because the championship team may not be representative of the entire league.
Answer:
Mean= 242.5 pounds
Median= 236 pounds
Mode= 208 and 278 pounds
Range=117 pounds
Mid-range= 58.5 pounds
B. The results are likely to be representative because a championship team is most likely representative of the entire league.
Step-by-step explanation:
278 303 186 292 276 205 208 236 278 198 208
Arranged in ascending order is
186 198 205 208 208 236 276 278 278 292 303
Mean = (186 +198+ 205+ 208 +208 +236 + 276+ 278 +278+ 292 +303)/11
Mean =2668/11
Mean= 242.5 pounds
Median = the middle number
Median= 236 pounds
Mode = highest occuring number(s)
Mode= 208 and 278 pounds
Range= highest number- smallest number
Range=303-186
Range=117 pounds
Mid-range= range/2
Mid-range= 117/2
Mid-range= 58.5 pounds
A hockey team is convinced that the coin used to determine the order of play is weighted. The team captain steals this special coin and flips it 14 times to evaluate the hypothesis that the coin is weighted, and it shows up heads 12 times. Test this hypothesis (use alpha=.05).
1. What is the appropriate test?
2. State the null hypothesis:
3. State the alternative hypothesis:
4. Find the critical value:
5. Calculate the obtained statistic:
6. Make a decision:
7. What does your decision mean
Answer:
Since x= 12 (0.006461) does not fall in the critical region so we accept our null hypothesis and conclude that the coin is fair.
Step-by-step explanation:
Let p be the probability of heads in a single toss of the coin. Then our null hypothesis that the coin is fair will be formulated as
H0 :p 0.5 against Ha: p ≠ 0.5
The significance level is approximately 0.05
The test statistic to be used is number of heads x.
Critical Region: First we compute the probabilities associated with X the number of heads using the binomial distribution
Heads (x) Probability (X=x) Cumulative Decumulative
0 1/16384 (1) 0.000061 0.000061
1 1/16384 (14) 0.00085 0.000911
2 1/16384 (91) 0.00555 0.006461
3 1/16384(364) 0.02222
4 1/16384(1001) 0.0611
5 1/16384(2002) 0.122188
6 1/16384(3003) 0.1833
7 1/16384(3432) 0.2095
8 1/16384(3003) 0.1833
9 1/16384(2002) 0.122188
10 1/16384(1001) 0.0611
11 1/16384(364) 0.02222
12 1/16384(91) 0.00555 0.006461
13 1/16384(14) 0.00085 0.000911
14 1/16384(1) 0.000061 0.000061
We use the cumulative and decumulative column as the critical region is composed of two portions of area ( probability) one in each tail of the distribution. If alpha = 0.05 then alpha by 2 - 0.025 ( area in each tail).
We observe that P (X≤2) = 0.006461 > 0.025
and
P ( X≥12 ) = 0.006461 > 0.025
Therefore true significance level is
∝= P (X≤0)+P ( X≥14 ) = 0.000061+0.000061= 0.000122
Hence critical region is (X≤0) and ( X≥14)
Computation x= 12
Since x= 12 (0.006461) does not fall in the critical region so we accept our null hypothesis and conclude that the coin is fair.
What is the intersection of the lines given by 2y=-x+3 and -y=5x+1? Enter the answer as an ordered pair.
Answer:
(-5/9, 16/9)
Step-by-step explanation:
2y = -x + 3
-y = 5x + 1
To find the intersection, you need to substitute the y-value from the second equation into the first equation. Rearrange the second equation so that it is equal to y.
-y = 5x + 1
-1(-y) = -1(5x + 1)
y = -5x - 1
Substitute this equation into the y-value of the first equation.
2y = -x + 3
2(-5x - 1) = -x + 3
-10x - 2 = -x + 3
(-10x - 2) + 2 = (-x + 3) + 2
-10x = -x + 5
(-10x) + x = (-x + 5) + x
-9x = 5
(-9x)/(-9) = (5)/(-9)
x = -5/9
Plug this x value into one of the equations and solve for y.
2y = -x + 3
2y = -(-5/9) + 3
2y = 5/9 + 3
2y = 32/9
(2y)/2 = (32/9)/2
y = 32/18 = 16/9
The ordered pair is (-5/9, 16/9).
A paint machine dispenses dye into paint cans to create different shades of paint. The amount of dye dispensed into a can is known to have a normal distribution with a mean of 5 milliliters (ml) and a standard deviation of 0.4 ml. Answer the following questions based on this information. Find the dye amount that represents the 9th percentile of the distribution.
Answer:
4.464 ml
Step-by-step explanation:
Given that:
mean (μ) = 5 mm, standard deviation (σ) = 0.4 ml
The z score is a score in statistics used to determine by how many standard deviation the raw score is above or below the mean. If the z score is positive then the raw score is above the mean and if the z score is negative then the raw score is below the mean It is given by:
[tex]z=\frac{x-\mu}{\sigma}[/tex]
From the normal distribution table, the 9th percentile (0.09) corresponds to a z score of -1.34
[tex]z=\frac{x-\mu}{\sigma}\\\\-1.34=\frac{x-5}{0.4}\\\\x-5=-0.536\\\\x=5-0.536\\\\x=4.464[/tex]
The dye amount that represents the 9th percentile of the distribution is 4.464 ml
Question 7
2 pts
Find the value of x and the length of segment AC if point B is between A and C.
AB = 5x, BC = 9x-2, AC = 11x + 7.6
Value of x=
Length of AC is
Answer: x=3.2 AC= 42.8
Step-by-step explanation:
As point B lies at segment AC AC=AB+BC
Otherwise we can write the equation
5x+9x-2=11x+7.6
14x-2=11x+7.6
14x-2+2=11x+7.6+2
14x=11x+9.6
14x-11x=11x-11x+9.6
3x=9.6
x=9.6:3
x=3.2
AC= 11*x+7.6= 11*3.2+7.6=35.2+7.6=42.8
Which of the following is an arithmetic sequence? A.-2, 4, -6, 8, ... B.2, 4, 8, 16, ... C.-8, -6, -4, -2, ...
Answer:
C. -8, -6, -4, -2, ...
Step-by-step explanation:
An arithmetic sequence increases by the same amount every time through addition or subtraction. There is a common difference.
A: -2, 4, -6, 8, ... If there were a common difference, the numbers would not switch between being positive and back to negative. The numbers would either keep going positive or keep going negative.
B: 2, 4, 8, 16, ... The common difference between 16 and 8 is 16 - 8 = 8. The difference between 8 and 4 is 8 - 4 = 4. Since the difference changes between the numbers, this is not an arithmetic sequence.
C. -8, -6, -4, -2, ... The common difference between -2 and -4 is -2 - (-4) = -2 + 4 = 2. The difference between -4 and -6 is -4 - (-6) = -4 + 6 = 2. The difference between -6 and -8 is -6 - (-8) = -6 + 8 = 2. Since the common difference is always two, this is an arithmetic sequence.
Hope this helps!
Aaron wants to mulch his garden. His garden is x^2+18x+81 ft^2 One bag of mulch covers x^2-81 ft^2 . Divide the expressions and simplify to find how many bags of mulch Aaron needs to mulch his garden.
Answer:
Step-by-step explanation:
Given
Garden: [tex]x^2+18x+81[/tex]
One Bag: [tex]x^2 - 81[/tex]
Requires
Determine the number of bags to cover the whole garden
This is calculated as thus;
[tex]Bags = \frac{x^2+18x+81}{x^2 - 81}[/tex]
Expand the numerator
[tex]Bags = \frac{x^2+9x+9x+81}{x^2 - 81}[/tex]
[tex]Bags = \frac{x(x+9)+9(x+9)}{x^2 - 81}[/tex]
[tex]Bags = \frac{(x+9)(x+9)}{x^2 - 81}[/tex]
Express 81 as 9²
[tex]Bags = \frac{(x+9)(x+9)}{x^2 - 9\²}[/tex]
Evaluate as difference of two squares
[tex]Bags = \frac{(x+9)(x+9)}{(x - 9)(x+9)}[/tex]
[tex]Bags = \frac{(x+9)}{(x - 9)}[/tex]
Hence, the number of bags is [tex]Bags = \frac{(x+9)}{(x - 9)}[/tex]
A school is holding a raffle to raise money to buy new books for the library. The school plans on awarding 18, $200 prizes, 120 $25 prizes and 270 $5 prizes. Is $10 enough to charge per ticket if they only sell 1000 tickets?
Answer:
Yes
Step-by-step explanation:
18 × 200 = 3600
120 × 25 = 3000
270 × 5 = 1350
in total 7950
tickets = 10 × 1000 = 10000
7950 < 10000
Please answer this correctly without making mistakes
Answer:
[tex]\large \boxed{\mathrm{1/2 \ boxes}}[/tex]
Step-by-step explanation:
Subtract the fractions.
[tex]\frac{9}{16}-\frac{1}{16}=\frac{8}{16} =\frac{1}{2}[/tex]
Vicky had 1/2 of a box more baking powder yesterday.
Varia is studying abroad in Europe. She is required pay $3,500 (in US dollars) per year to the university; however, she must pay in euros. How many euros can Varia expect to pay per month to the university?
Answer: 247.92 euros
Step-by-step explanation:
Given, Varia is required pay $3,500 (in US dollars) per year to the university.
If she must pay in euros , then we convert $3,500 into euros.
Current rate : 1 US dollar = 0.85 euro
Then, $3,500 = ( 0.85 x 3500) euros
= 2975 euros
She can expect 2975 euros to pay per year.
Also, [tex]2975\div 12\approx247.92[/tex] [ 1 years = 12 months]
Hence, She can expect 247.92 euros to pay per month to the university.
One way to calculate the target heart rate of a physically fit adult during exercise is given by the formula h=0.8( 220−x ), where h is the number of heartbeats per minute and x is the age of the person in years. Which formula is equivalent and gives the age of the person in terms of the number of heartbeats per minute?
Answer:
The answer is:
C. [tex]\bold{x = -1.25h+220}[/tex]
Step-by-step explanation:
Given:
[tex]h=0.8( 220-x )[/tex]
Where [tex]h[/tex] is the heartbeats per minute and
[tex]x[/tex] is the age of person
To find:
Age of person in terms of heartbeats per minute = ?
To choose form the options:
[tex]A.\ x=176-h\\B.\ x=176-0.8h\\C.\ x=-1.25h+220\\D.\ x=h-0.8220[/tex]
Solution:
First of all, let us have a look at the given equation:
[tex]h=0.8( 220-x )[/tex]
It is value of [tex]h[/tex] in terms of [tex]x[/tex].
We have to find the value of [tex]x[/tex] in terms of [tex]h[/tex].
Let us divide the equation by 0.8 on both sides:
[tex]\dfrac{h}{0.8}=\dfrac{0.8( 220-x )}{0.8}\\\Rightarrow \dfrac{1}{0.8}h=220-x\\\Rightarrow 1.25h=220-x[/tex]
Now, subtracting 220 from both sides:
[tex]\Rightarrow 1.25h-220=220-x-220\\\Rightarrow 1.25h-220=-x[/tex]
Now, multiplying with -1 on both sides:
[tex]-1.25h+220=x\\OR\\\bold{x = -1.25h+220}[/tex]
So, the answer is:
C. [tex]\bold{x = -1.25h+220}[/tex]
Nour drove from the Dead Sea up to Amman, and her altitude changed at a constant rate. When she began driving, her altitude was 400400400 meters below sea level. When she arrived in Amman 222 hours later, her altitude was 100010001000 meters above sea level. Let yyy represent Nour's altitude (in meters) relative to sea level after xxx hours.
Answer:
y = 700x - 400
Step-by-step explanation:
A negative number represents an altitude below sea level.
Beginning: -400
y = mx + b
y = mx - 400
In 2 hours the altitude was now 1000 m.
1000 m - (400 m) = 1400 m
The altitude went up 1400 m in 2 hours. The rate of change is
1400/2 m/h = 700 m/h
The rate of change is the slope.
y = 700x - 400
Answer:
The graph answer is below :)
Step-by-step explanation:
Musah stands at the centre of a rectangular field. He first takes 50 steps north, then 25 steps
west and finally 50 steps on a bearing of 3150
.
i. Sketch Musah’s movement
Answer:
Step-by-step explanation:
Following the cardinal points as regards location of points, the sketch of Musah's movement can be as what is attached to this answer.
Using the FOIL method, find the product of x - 2 and x - 3 .
Answer:
[tex] \boxed{ {x}^{2} - 5x + 6}[/tex]Step-by-step explanation:
[tex] \mathsf{(x - 2)(x - 3)}[/tex]
Multiply each term in the first parentheses by each term in the second parentheses ( FOIL )
[tex] \mathsf{x×x - 3x - 2x - 2 × ( - 3 )}[/tex]
Calculate the product
[tex] \mathsf{ {x}^{2} - 3x - 2x - 2 \times (- 3)}[/tex]
Multiply the numbers
[tex] \mathsf{ {x}^{2} - 3x - 2x + 6 }[/tex]
Collect like terms
[tex] \mathsf{ {x}^{2} - 5x + 6}[/tex]
Hope I helped!
Best regards!
Mark is buying supplies for his students. He is buying a notebook (n) and a pack of pencils for each of his 25 students. Each pack of pencils costs $1.25. If Mark's total cost is $156.25, which of the following equations can be used to find how much each notebook cost? Select TWO that apply.
Answer:
$5
Step-by-step explanation:
Note. There are no options to select.Let the notebook cost x, then Mark spent:
25x + 25*1.25 = 156.2525x + 31.25 = 156.2525x = 156.25 - 31.2525x = 125x= 125/25x= 5Notebook costs $5
Let A and B be any two sets. Show that:
Show that (
AUB)', (BUA)' = 0
Step-by-step explanation:
(AUB)' means they are all outside the set A and B so thats 0. Hope it helps
Karl needs a total of $30 to buy a bike. He has $12. He can earn $6 an hour
babysitting. Which equation can be used to find the number of hours, h, Karl has to
babysit to have the money he needs?
30 - 6h + 12 = 0
6+ n = 12
6 + 12 h = 30
6 h + 12 = 30
Answer:
6h + 12 = 30
Step-by-step explanation:
Hence, the equation obtained for number of hours worked is given as 12 + 6h = 30.
How to write a linear equation?A linear equation for the given case can be written by assuming any variable as the unknown quantity. Then, as per the given data the required operations are done and it is equated to some value.
The total money required is given as $30.
Suppose the number of hours for babysitting be h.
Then, the money earned by doing it is $6h.
And, the total money with Karl is 12 + 6h.
As per the question, the following equations can be written as,
12 + 6h = 30
Hence, the equation for finding the number of hours is given as 12 + 6h = 30.
To know more about linear equation click on,
https://brainly.com/question/11897796
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For what values of y: Is the value of the fraction 5−2y 12 always greater than the value of 1−6y?
Answer:
[tex](5 - 2y) \div 12 > 1 - 6y[/tex]
[tex]5 - 2y > 12 - 72y[/tex]
[tex] - 7 > - 70y[/tex]
[tex]7 < 70y[/tex]
[tex]y > 1 \div 10 = 0.1[/tex]
the temperature at which water freezes on the celsius scale is 0 degrees C. It freezes at 32 degrees F on the Fahrenheit scale, write opposites fo these two numbers as integers.
Answer:
If we have an integer number N, the opposite of N will be:
-1*N = -N.
Then, the opposite of 0°C is:
-1*0°C = 0°C.
The number 0 is it's own opposite.
And for 32F, the opposite is:
-1*32F = -32F
So, while the numbers 0°C and 32F physically represent the same thing (the same temperature), mathematically, they behave differently.
The amount of money spent on textbooks per year for students is approximately normal.
a. To estimate the population mean, 19 students are randomly selected the sample mean was $390 and the standard deviation was $120. Find a 95% confidence for the population meam.
b. If the confidence level in part a changed from 95% 1to1999%, would the margin of error for the confidence interval (mark one answer): decrease stay the same increase not enough information to answer
c. If the sample size in part a changed from 19 10 22. would the margin of errot for the confidence interval (mark one answer): decrease in stay the same increase in not enough information to answer
d. To estimate the proportion of students who purchase their textbookslused, 500 students were sampled. 210 of these students purchased used textbooks. Find a 99% confidence interval for the proportion of students who purchase used text books.
Answer:a
a
[tex]336.04 < \mu < 443.96[/tex]
b
The margin of error will increase
c
The margin of error will decreases
d
The 99% confidence interval is [tex]0.4107 < p < 0.4293[/tex]
Step-by-step explanation:
From the question we are told that
The sample size [tex]n = 19[/tex]
The sample mean is [tex]\= x = \$\ 390[/tex]
The standard deviation is [tex]\sigma = \$ \ 120[/tex]
Given that the confidence level is 95% then the level of significance is mathematically represented as
[tex]\alpha = 100 - 95[/tex]
[tex]\alpha = 5 \%[/tex]
[tex]\alpha = 0.05[/tex]
Next we obtain the critical value of [tex]\frac{\alpha }{2}[/tex] from the normal distribution table
So
[tex]Z_{\frac{\alpha }{2} } = 1.96[/tex]
The margin of error is mathematically represented as
[tex]E = Z_{\frac{\alpha }{2} } * \frac{\sigma}{\sqrt{n} }[/tex]
=> [tex]E = 1.96 * \frac{120}{\sqrt{19} }[/tex]
=> [tex]E = 53.96[/tex]
The 95% confidence interval is
[tex]\= x - E < \mu < \= x + E[/tex]
=> [tex]390 - 53.96 < \mu < 390 - 53.96[/tex]
=> [tex]336.04 < \mu < 443.96[/tex]
When the confidence level increases the [tex]Z_{\frac{\alpha }{2} }[/tex] also increases which increases the margin of error hence the confidence level becomes wider
Generally the sample size mathematically varies with margin of error as follows
[tex]n \ \ \alpha \ \ \frac{1}{E^2 }[/tex]
So if the sample size increases the margin of error decrease
The sample proportion is mathematically represented as
[tex]\r p = \frac{210}{500}[/tex]
[tex]\r p = 0.42[/tex]
Given that the confidence level is 0.99 the level of significance is [tex]\alpha = 0.01[/tex]
The critical value of [tex]\frac{\alpha }{2}[/tex] from the normal distribution table is
[tex]Z_{\frac{\alpha }{2} } = 2.58[/tex]
Generally the margin of error is mathematically represented as
[tex]E = Z_{\frac{\alpha }{2} }* \sqrt{ \frac{\r p (1- \r p )}{n} }[/tex]
=> [tex]E = 0.42 * \sqrt{ \frac{0.42 (1- 0.42 )}{ 500} }[/tex]
=> [tex]E = 0.0093[/tex]
The 99% confidence interval is
[tex]\r p - E < p < \r p + E[/tex]
[tex]0.42 - 0.0093 < p < 0.42 + 0.0093[/tex]
[tex]0.4107 < p < 0.4293[/tex]
A random sample of size 100 is taken from a population described by the proportion p = 0.60. The probability that the sample proportion is less than 0.55 is ________.
Answer:hope it helps
Step-by-step explanation:
Result:
0.6
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Plain Text
Number line:
Number line
Rational form:
3/5
Please answer this correctly without making mistakes
Answer:
1/2 mi
Step-by-step explanation:
Fairfax to Greenwood is equal to one mile
Now think of it as an equation and substitute 1/2 for fairfax and x for greenwood
1/2 + x = 1
This means that x = 1/2
Because of this from Arcadia to Greenwood it is 1/2 mi
