You flip two coins. What is the probability
that you flip at least one head?
​

Answer:

A) Q(t) = 4e^-(0.0079t)

B) t = 115.99 ≈ 116

Therefore scientist will be able to receive data after 116 years

Step-by-step explanation:

a)

to write a function of the form Q(t)= Q₀e⁻^kt to model the quantity Q(t) of ²³⁸Pu left after t-years.

so given that; half-life of ²³⁸Pu is 87.7 years,

∴ t =  87.7 years , Q(t) = 0.5Q₀

Now we substitute these value in the form  Q(t)= Q₀e⁻^kt

Q(t)= Q₀e⁻^kt

0.5Q₀ = Q₀e^ -(87.7k)

0.5 = e^ -(87.7k)

now we take the natural logarithm of both sides

In(0.5) = Ine^ -(87.7k)

Now using the property logₙnᵃ = a

-87.7k = In(0.5)

k = - In(0.5) / 87.7

k = 0.0079

ALSO it was given that Q₀ = 4.0 kg

Therefore , model quality Q(t) of ²³⁸pu left after t years is:

Q(t) = 4e^-(0.0079t)

b)

to find the time left after 1.6kg of ²³⁸pu

we simple substitute  Q(t) = 1.6 into Q(t) = 4e^-(0.0079t)

so we have

1.6 = 4e^-(0.0079t)

e^-(0.0079t) = 1.6/4

e^-(0.0079t) = 0.4

again we take the natural logarithm of both sides,

Ine^-(0.0079t) = In(0.4)

again using the property logₙnᵃ = a

-0.0079t = In(0.4)

t = - in(0.4) / 0.0079

t = 115.99 ≈ 116

Therefore scientist will be able to receive data after 116 years

Answer:the mean is greater than the median

Step-by-step explanation:

The mean is less than the median. Then the correct option is A.

Statistics is the study of collection, analysis, interpretation, and presentation of data or to discipline to collect, and summarise the data.

Half the students scored 87.  

The next highest score is 71.

Then the median will be

(71+ 87) / 2 = 79

A few students scored 52, so the mean is slightly lower than the mean of 71 and 87.

Thus, the mean is less than the median.

Then the correct option is A.

The missing options are given below.

A. The mean is less than the median.

B. The mean and the median is the same.

C. The mean is greater than the mode.

D. The mean is greater than the median.

More about the statistics link is given below.

https://brainly.com/question/10951564

#SPJ2

Complete question :

The development of AstroWorld ("The Amusement Park of the Future") on the outskirts of a city will increase the city's population at the rate given below in people/year t yr after the start of construction. 5,700√t + 11,000 The population before construction is 67,000. Determine the projected population 16 yr after the construction of the park has begun. people

Answer:

486,200

Step-by-step explanation:

Given that the rate of change in population is represented by the function:

f(t) = 5,700√t + 11,000

To get the original function, we take the integral of the rate function because the rate of change is obtained by taking the derivate of the original equation

f(t) = 5,700t^1/2 + 11,000

Taking the integral of f with respect to t:

∫(5,700t^1/2 + 11,000)

[5700t^(1/2 + 1)] / (1/2 + 1) + 11000t + C

[(5700t^3/2)/ 3/2] + 11000t + C

Where C = constant

If population before construction = 67000

Then C = 67000

t = time = 16 years

Substitute values into the original change equation:

[(5700(16)^3/2)/ 3/2] + 11000t + 67000

[(5700 * 64) / 1.5] + 11000(16) + 67000

243200 + 176000 + 67000

= 486,200

Answer:

3x18 = 3 (10+8) is an example of the commutative property of multiplication

Step-by-step explanation:

Answer: commutative property of multiplication

Step-by-step explanation:

Answer:

No

It could be purely due to chance.

Step-by-step explanation:

A population is defined as the whole group which has the same characteristics. For example a population of the college belongs to the same college . But a sample may be an element of a population.

So it is not necessary for a population to have the same characteristics as the sample.

But it is essential for the sample to have at least one same characteristics as the population.

So we would not be correct in inferring that such a relationship also exists in the population.

It is a hypothesis which can be true or false due to certain conditions or limitations as the case maybe.

For example in a population of smokers some may be in the habit of taking cocaine. But a sample of cocaine users does not mean the whole population uses it.

It could be purely due to chance if we find out that there is a relationship between parents’ and children’s party identification in the population.

Answer:

2.5 meters

Step-by-step explanation:

Answer:

Mass= 6kg

Acceleration= 10 ms^-2

Work done = 1200Nm

Step-by-step explanation:

kg*m/s^2 represent the force.

The kg represent the mass

The m/s^2 represent the acceleration

The acceleration here will be due to gravity force= 10 ms^-2

Then the mass= 60/10

Mass= 6 kg

The force = 60 Newton

Distance covered in the direction of the the force= 20 Meters

The work done in the direction of the force= force* distance

The work done in the direction of the force=60*20

The work done in the direction of the force=1200 Nm

Answer: 20 • 60

Step-by-step explanation:

Let assume that the mean is 184 and the standard deviation is 6

Heights of men on a baseball team have a​ bell-shaped distribution with a mean 184 of and a standard deviation of 6 . Using the empirical​ rule, what is the approximate percentage of the men between the following​ values? a.166 cm and 202 cm b. 172 cm and 196cm

Answer:

P(156<X<202) =  99.7%

P(172<X<196) =  95.5%

Step-by-step explanation:

Given that :

Heights of men on a baseball team have a​ bell-shaped distribution with a mean of and a standard deviation of . Using the empirical​ rule, what is the approximate percentage of the men between the following​ values? a.166 cm and 202 cm b. 172 cm and 196cm

For a.

Using the empirical​ rule, what is the approximate percentage of the men between the following​ values 166 cm and 202 cm.

the z score can be determined by using the formula:

[tex]z = \dfrac{X - \mu}{\sigma}[/tex]

[tex]z(166) = \dfrac{166-184}{6}[/tex]

[tex]z(166) = \dfrac{-18}{6}[/tex]

z(166) = -3

[tex]z(202) = \dfrac{202-184}{6}[/tex]

[tex]z(202) = \dfrac{18}{6}[/tex]

z(202) = 3

P(156<X<202) = P( μ - 3σ < X < μ + 3σ )

P(156<X<202) = P( - 3 < Z < 3)

P(156<X<202) = P( Z <  3) - P(Z < -3)

P(156<X<202) = 0.99865-  0.001349

P(156<X<202) =  0.997301

P(156<X<202) =  99.7%

For b.

b. 172 cm and 196cm

[tex]z = \dfrac{X - \mu}{\sigma}[/tex]

[tex]z(172) = \dfrac{172-184}{6}[/tex]

[tex]z(172) = \dfrac{-12}{6}[/tex]

z(172) = -2

[tex]z(196) = \dfrac{196-184}{6}[/tex]

[tex]z(196) = \dfrac{12}{6}[/tex]

z(196) = 2

P(172<X<196) = P( μ - 2σ < X < μ + 2σ )

P(172<X<196) = P( - 2 < Z < 2)

P(172<X<196) = P( Z <  2) - P(Z < -2)

P(172<X<196) = 0.9772 -  0.02275

P(172<X<196) =  0.95445

P(172<X<196) =  95.5%

Answer: y=(4/3)x+2/3

Step-by-step explanation:

Slope-intercept form is expressed as y=mx+b

First, find the slope (m):

m= rise/run or vertical/horizontal or y/x (found between the highlighted points)

m = 4/3

Second, find b:

Use one of the highlighted points for (x, y)

2=4/3(1)+b

6/3=4/3+b

2/3=b

b=2/3

Plug it into the equation:

You get y=(4/3)x+2/3 :)

Complete question is;

A manufacturer claims that the calling range (in feet) of its 900-MHz cordless telephone is greater than that of its leading competitor. A sample of 19 phones from the manufacturer had a mean range of 1160 feet with a standard deviation of 32 feet. A sample of 11 similar phones from its competitor had a mean range of 1130 feet with a standard deviation of 30 feet. Required:

Do the results support the manufacturer's claim?

Let μ1 be the true mean range of the manufacturer's cordless telephone and μ2 be the true mean range of the competitor's cordless telephone. Use a significance level of α = 0.01 for the test. Assume that the population variances are equal and that the two populations are normally distributed

Answer:

We will fail to reject the null hypothesis as there is no sufficient evidence to support the manufacturers claim.

Step-by-step explanation:

For the first sample, we have;

Mean; x'1 = 1160 ft

standard deviation; σ1 = 32 feet

Sample size; n1 = 19

For the second sample, we have;

Mean; x'2 = 1130 ft

Standard deviation; σ2 = 30 ft

Sample size; n2 = 11

The hypotheses are;

Null Hypothesis; H0; μ1 = μ2

Alternative hypothesis; Ha; μ1 > μ2

The test statistic formula for this is;

z = (x'1 - x'2)/√[(σ1)²/n1) + (σ2)²/n2)]

Plugging in the relevant values, we have;

z = (1160 - 1130)/√[(32)²/19) + (30)²/11)]

z = 2.58

From the z-table attached, we have a p-value = 0.99506

This p-value is more than the significance value of 0.01,thus,we will fail to reject the null hypothesis as there is no sufficient evidence to support the manufacturers claim.

Answer:

the standard deviation of the sample is less than  0.1

Step-by-step explanation:

Given that :

The sample size n = 100 units

The average proportion of non-conforming windshield wipers is found to be 0.042 which is the defective rate P-bar

The standard deviation of the machine([tex]S_p[/tex]) can be calculated  by using the formula:

[tex]S_p =\dfrac{ \sqrt{ \overline P \times (1 - \overline P)} }{n}[/tex]

[tex]S_p =\dfrac{ \sqrt{0.042 \times (1 -0.042)} }{100}[/tex]

[tex]S_p =\dfrac{ \sqrt{0.042 \times (0.958)} }{100}[/tex]

[tex]S_p =\dfrac{ \sqrt{0.040236} }{100}[/tex]

[tex]S_p =\dfrac{ 0.2005891323 }{100}[/tex]

[tex]S_p =0.002[/tex]

Thus , the standard deviation of the sample is less than  0.1

Answer:

2.67 miles (or 8/3 miles which is also 3 2/3 miles)

Step-by-step explanation:

S (shane) = 7

L (lissette) = ??

S = 3(L) - 1

7 = 3L - 1

8 = 3L

L = 2.67 miles

Answer:

288

Step-by-step explanation:

Area of two triangles=2(½bh)

=bh

=8×6

=48

For the rectangles=lb + lb +lb

l(b+b+b)

=12(8+6+6)

=12×20

=240

Total area=240 +48=288

Answer:

i think

x=6.77

y=11.33

Answer: stratified

Step-by-step explanation:

In stratified sampling, you divide the population into subgroups, or strata, with similar characteristics, like here we have divided the population into subgroups that depend on their political alignment. This is used when you can expect that the results have a noticeable variation between the different subgroups. Usually, you want to have the same number of population for eac subgroup, but sometimes it is hard for different reasons (not enough people in one subgroup, for example)

In cluster sampling we also use subgroups, but the subgroup itself is the unit of the sampling, while in this case, we are randomly selecting individuals of the given subgroups.

So this would be a "stratified sampling".

Answer:

[tex]-1 \frac{3}{4}[/tex]

Step-by-step explanation:

Using this number line, we can plot our original number - [tex]\frac{3}{4}[/tex] (see picture attached)

Adding a negative is the same thing as subtracting - so we are subtracting [tex]2\frac{1}{2}[/tex] from  [tex]\frac{3}{4}[/tex].

To subtract this, we can break up [tex]2\frac{1}{2}[/tex]  into 3 parts: 1, 1, and [tex]\frac{1}{2}[/tex]. We can subtract each of these from the current number and see where we land up. (again see picture)

We land up at [tex]-1 \frac{3}{4}[/tex].

Hope this helped!

Answer:

1   [tex]\sigma_{\= x } = 0.0130[/tex]

2  [tex]n = 3908.5[/tex]

Step-by-step explanation:

From the question we are told that

     The  sample size is  [tex]n_p = 1400[/tex]

      The  number of those that said the would use internet is [tex]k = 872[/tex]

       The margin of error is  [tex]E = 0.02[/tex]

Generally the sample proportion is mathematically evaluated as

            [tex]\r p = \frac{k}{n_p}[/tex]

substituting values

            [tex]\r p = \frac{ 872}{1400}[/tex]

substituting values

           [tex]\r p = 0.623[/tex]

Generally the standard error of  [tex]\r p[/tex] is mathematically evaluated as

           [tex]\sigma_{\= x } = \sqrt{\frac{\r p (1- \r p)}{n} }[/tex]

substituting values

              [tex]\sigma_{\= x } = \sqrt{\frac{0.623 (1- 0.623)}{1400} }[/tex]

              [tex]\sigma_{\= x } = 0.0130[/tex]

For  a  95% confidence interval the confidence level is  95%

Given that the confidence interval is 95% the we can evaluated the level of confidence as

                    [tex]\alpha = 100 - 99[/tex]

                   [tex]\alpha = 1\%[/tex]

                   [tex]\alpha = 0.01[/tex]

Next we obtain the critical value of  [tex]\frac{\alpha }{2}[/tex] from normal distribution table (reference math dot  armstrong dot edu) , the value is  

         [tex]Z_{\frac{\alpha }{2} } = 2.58[/tex]

Give that the population size is very large  the sample size is mathematically represented as

            [tex]n = [ \frac{Z_{\frac{\alpha }{2} ^2 * \r p ( 1 - \r p )}}{E^2} ][/tex]

substituting values  

             [tex]n = [ \frac{2.58 ^2 * 0.623 ( 1 -0.623 )}{0.02^2} ][/tex]

             [tex]n = 3908.5[/tex]

Answer:

f(x) = x^2 - 3x -10

Step-by-step explanation:

If the solutions are {-2, 5}, the factors of the quadratic are (x + 2) and (x - 5).

The equation is f(x) = (x + 2)(x - 5) = x^2 - 3x -10

Answer:

60 pounds

Step-by-step explanation:

Let x = number of pounds of grass seeds A

The number of pounds of grass seed B = 140 pounds

Total pounds of the resulting mixture = (140 + x) pounds

Rye grass A = 60% = 0.6

Rye grass B = 80% = 0.8

Total percent of mixture formed = 74% = 0.74

Hence, we have the equation:

0.6x + 0.8 × 140 = 0.74 ( 140 + x)

0.6x + 112 = 103.6 + 0.74x

Collect like terms

112 - 103.6 = 0.74x - 0.6x

8.4 = 0.14x

x = 60 pounds

Therefore, the quantity of the 60% mixture used is 60 pounds.

The manager of a garden shop mixes grass seed that is 60% rye grass with 140 pound of grass seed that is 80% rye grass to make a mixture that is 74% rye grass. How much of the 60% mixture is used?

Answer:

Step-by-step explanation:

Since the above figure is a right angled triangle we can use trigonometric ratios to find y

To find y we use tan

tan∅ = opposite/ adjacent

From the question

the opposite is y

the adjacent is 350 ft

Substitute the values into the above formula

That's

[tex] \tan(27) = \frac{y}{350} [/tex]

y = 350 tan 27

y = 178.3339

We have the final answer as

Hope this helps you

Answer:

When a shape is congruent they are equal in shape, size, and measure. Although if a shape is similar they will be the same shape, but not the same size, instead they will be proportionate.

Step-by-step explanation:

Answer:

CongruentCongruent figures are identical in size, shape and measure. SimilarTwo figures are similar if they have the same shape, but not necessarily the same size.

Step-by-step explanation:

Answer:

(-1,-4)

Step-by-step explanation:

The equation of a parabola os written as: ax^2+bx+c

This parabola's equation is x^2+2x-3

● a= 1

● b= 2

● c = -3

The coordinates of the parabola are: ( (-b/2a) ; f(-b/2a) )

● -b/2a = -2/2 = -1

● f(-b/2a) = (-1)^2+2×(-1)-3=1-2-3= -4

So the vertex coordinates are (-1,-4)

Answer:

-1+2X

Step-by-step explanation:

Answer:

Hey there!

The x coordinate would be -5.

Let me know if this helps :)

As we can see in the Graph,

y-coordinate = - 7

Answer

$25.59

Step-by-step explanation:

subtract by percentage or you can also do:

100% - 4.5% = 95.5%

95.5% x $26.80 = $25.594

IF ROUNDED: $25.59

Answer:

$25.65

Step-by-step explanation:

Let the original hourly rate be r.  

Then 1.045r + $26.80/hr.

Dividing both sides by 1.045, we get:

      $26.80/hr

r = ------------------ = $25.65  This was the before-raise pay rate.

         1.045

Answer:

Solution : Option D

Step-by-step explanation:

The first thing we want to do here is isolate the cos(t) and sin(t) for both the equations --- ( 1 )

x = 5cos(t) ⇒ x / 5 = cos(t)

y = 2sin(t) ⇒ y / 2 = sin(t)

Let's square both equations now. Remember that cos²t + sin²t = 1. Therefore, we can now add both equations after squaring them --- ( 2 )

( x / 5 )² = cos²(t)

+ ( y / 2 )² = sin²(t)

_____________

x² / 25 + y² / 4 = 1

Remember that addition indicates that the conic will be an ellipse. Therefore your solution is option d.

Answer:

Explanation

There are some activities in Courseware content that report scores and some that just report mastery and/or completion status.

Resolution

Dynamic vs. Non-dynamic mastery tests

Mastery tests give mastery status if the score is 80% or higher, but not all tests report a score. There are two types of mastery tests in Courseware content:

Non-dynamic tests: Those that do report a score, such as those in the Writing Process and Practice titles, in the Grammar and Mechanics modules, give the same number of questions each time; these are non-dynamic tests. For example, Splitting Fused Run-ons: Mastery Test presents ten questions. Even if the Learner answers the first three questions incorrectly and is, at that point, no longer able to answer eight correctly to achieve mastery, the remaining seven questions are presented.

Dynamic tests: Mastery tests from some content titles, such as Essential Reading Skills, however, are dynamic, which means they adapt to the Learner's responses. These tests do not always give the maximum number of questions; instead, they will end sooner if 80% is either achieved or no longer achievable. These tests show mastery if 80% or better was achieved, but do not show a score. For example, in Essential Reading Skills, Pronouns: Mastery Test, the maximum number of questions presented is five; mastery requires four questions are answered correctly. The test will end early if the student answers the first four correctly or two incorrectly out of the first four. Mastery is still based on achieving 80% or better, but the score is not fully determined, so no score is reported, by design.

Step-by-step explanation:

Answer:

Option (4)

Step-by-step explanation:

Given sequence is,

[tex]1+\frac{3}{2}+\frac{9}{4}..........[/tex]

We can rewrite this sequence as,

[tex]1+\frac{3}{2}+(\frac{3}{2})^2.............[/tex]

There is a common ratio between the successive term and the previous term,

r = [tex]\frac{\frac{3}{2}}{1}[/tex]

r = [tex]\frac{3}{2}[/tex]

Therefore, it's a geometric sequence with infinite terms. In other words it's a geometric series.

Since sum of infinite geometric sequence is represented by the formula,

[tex]S_{n}=\frac{a}{1-r}[/tex]  , when r < 1

where 'a' = first term of the sequence

r = common ratio

Since common ratio of the given infinite series is greater than 1 which makes the series divergent.

Therefore, sum of infinite terms of a series will be infinite Or the sum is not possible.

Option (4) will be the answer.

Answer:

75%

Step-by-step explanation:

75% of possibility to have gold coin

Answer:

8[2]×88888

Step-by-step explanation:

[8×8]=8[2]×88888