a small book publisher knows that 15 books weigh 29 lbs. How much do 31 books weigh?

Answers

Answer 1

Answer:

I believe the answer would be 59.93333


Related Questions

What is the vertex of the graph of y+2x+3=-(x+2)^2+1

Answers

Answer:

(-3, 3)

Step-by-step explanation:

a number cube is rolled 2 times in a row. What is the probability of rolling a number greater than 2 both times?

Answers

Answer:

70%

Step-by-step explanation:

Answer:

The probability of rolling a number greater than 2 two times in a row is arond 0.44

Step-by-step explanation:

Divide the number of events by the number of possible outcomes. This will give us the probability of a single event occurring. In the case of rolling a 3 on a die, the number of events is 1 (there's only a single 3 on each die), and the number of outcomes is 6.

Probability formula is the ratio of number of favorable outcomes to the total number of possible outcomes. Measures the likelihood of an event in the following way: - If P(A) > P(B) then event A is more likely to occur than event B. - If P(A) = P(B) then events A and B are equally likely to occur.

Find the area of a trapezoid with base lengths 3 and 5 and heigh of 9

Answers

A trapezoid is a quadrilateral with exactly one pair of parallel sides.

Formula for area: [tex]A = \frac{1}{2}(^{b}1 + ^{b}2)(h)[/tex]

In this formula, the bases are the parallel sides.

Now plug the information into the formula.

[tex]A = \frac{1}{2} (3 + 5)(9)[/tex].

Follow your order of operations, simplify inside the parentheses first.

[tex]A = \frac{1}{2}(8)(9)[/tex].

(1/2)(8) is 4 so we have (4)(9) which is 36.

So the area of the trapezoid is 36.

Evaluate the following Integrals ∫sin

Answers

Answer:

[tex]\displaystyle \int {xsinx} \, dx = -xcosx + sinx + C[/tex]

General Formulas and Concepts:

Calculus

Differentiation

DerivativesDerivative Notation

Basic Power Rule:

f(x) = cxⁿf’(x) = c·nxⁿ⁻¹

Integration

IntegralsIndefinite IntegralsIntegration Constant C

Integration Property [Multiplied Constant]:                                                         [tex]\displaystyle \int {cf(x)} \, dx = c \int {f(x)} \, dx[/tex]

Integration by Parts:                                                                                               [tex]\displaystyle \int {u} \, dv = uv - \int {v} \, du[/tex]

[IBP] LIPET: Logs, inverses, Polynomials, Exponentials, Trig

Step-by-step explanation:

Step 1: Define

Identify

[tex]\displaystyle \int {xsinx} \, dx[/tex]

Step 2: Integrate Pt. 1

Identify variables for integration by parts using LIPET.

Set u:                                                                                                             [tex]\displaystyle u = x[/tex][u] Differentiate [Basic Power Rule]:                                                             [tex]\displaystyle du = dx[/tex][dv] Trigonometric Integration:                                                                     [tex]\displaystyle v = -cosx[/tex]Set dv:                                                                                                           [tex]\displaystyle dv = sinx \ dx[/tex]

Step 3: Integrate Pt. 2

[Integral] Integration by Parts:                                                                       [tex]\displaystyle \int {xsinx} \, dx = -xcosx - \int {-cosx} \, dx[/tex][Integral] Rewrite [Integration Property - Multiplied Constant]:                 [tex]\displaystyle \int {xsinx} \, dx = -xcosx + \int {cosx} \, dx[/tex][Integral] Trigonometric Integration:                                                             [tex]\displaystyle \int {xsinx} \, dx = -xcosx + sinx + C[/tex]

Topic: AP Calculus AB/BC (Calculus I/I + II)

Unit: Integration

Book: College Calculus 10e

For each of the following research scenarios, decide whether the design uses a related sample. If the design uses a related sample, identify whether it uses matched subjects or repeated measures. (Note: Researchers can match subjects by matching particular characteristics, or, in some cases, matched subjects are naturally paired, such as siblings or married couples.)John Caccioppo was interested in possible mechanisms by which loneliness may have deterious effects of health. He compared the sleep quality of a random sample to lonely people to the sleep quality of a random sample of nonlonely people.
The design described ______a, b, or c_________________________.
a. does not use a related sample
b. uses a related sample (repeated measures)
c. uses a related sample (matched subjects)

Answers

Answer:

The correct option is (a).

Step-by-step explanation:

The dependent t-test (also known as the paired t-test or matched-samples t-test) compares the two means associated groups to conclude if there is a statistically significant difference amid these two means.

We use the paired t-test if we have two measurements on the same item, person or thing. We should also use this test if we have two items that are being measured with a unique condition.

For instance, an experimenter tests the effect of a medicine on a group of patients before and after giving the doses.

In this case the researcher selected a random sample of the sleep quality of  lonely people and the random sample of the sleep quality of non-lonely people.

Both the sample in this case are selected from two very different population.

This clearly indicates that the study design is for non-related samples.

Thus, the correct option is (a).

A researcher finds that of 1000 people who said that they attend a religious service at least once a week, A stopped to help a person with car trouble. Of 1200 people interviewed who had not attended a religious service at least once a month, B stopped to help a person with car trouble. At the 0.05 significance level, test the claim that the two proportions are equal.

Answers

Answer:

There is enough evidence to support the claim that the proportions are not equal. (P-value: 0.048).

Step-by-step explanation:

The question is incomplete:

"A researcher finds that of 1000 people who said that they attend a religious service at least once a week, 31 stopped to help a person with car trouble. Of 1200 people interviewed who had not attended a religious service at least once a month, 22 stopped to help a person with car trouble. At the 0.05 significance level, test the claim that the two proportions are different."

This is a hypothesis test for the difference between proportions.

The claim is that the proportions are not equal.

Then, the null and alternative hypothesis are:

[tex]H_0: \pi_1-\pi_2=0\\\\H_a:\pi_1-\pi_2\neq 0[/tex]

The significance level is 0.05.

The sample 1, of size n1=1000 has a proportion of p1=0.031.

[tex]p_1=X_1/n_1=31/1000=0.031[/tex]

The sample 2, of size n2=1200 has a proportion of p2=0.018.

[tex]p_2=X_2/n_2=22/1200=0.018[/tex]

The difference between proportions is (p1-p2)=0.013.

[tex]p_d=p_1-p_2=0.031-0.018=0.013[/tex]

The pooled proportion, needed to calculate the standard error, is:

[tex]p=\dfrac{X_1+X_2}{n_1+n_2}=\dfrac{31+22}{1000+1200}=\dfrac{53}{2200}=0.024[/tex]

The estimated standard error of the difference between means is computed using the formula:

[tex]s_{p1-p2}=\sqrt{\dfrac{p(1-p)}{n_1}+\dfrac{p(1-p)}{n_2}}=\sqrt{\dfrac{0.024*0.976}{1000}+\dfrac{0.024*0.976}{1200}}\\\\\\s_{p1-p2}=\sqrt{0+0}=\sqrt{0}=0.007[/tex]

Then, we can calculate the z-statistic as:

[tex]z=\dfrac{p_d-(\pi_1-\pi_2)}{s_{p1-p2}}=\dfrac{0.013-0}{0.007}=\dfrac{0.013}{0.007}=1.98[/tex]

This test is a two-tailed test, so the P-value for this test is calculated as (using a z-table):

[tex]P-value=2\cdot P(z>1.98)=0.048[/tex]

As the P-value (0.048) is smaller than the significance level (0.05), the effect is significant.

The null hypothesis is rejected.

There is enough evidence to support the claim that the proportions are not equal.

Answer the question and do it correctly!

Answers

Answer:

2.4

Step-by-step explanation:

PEMDAS

(Parentheses) 6 + -5.8 = 0.2

(Multiplication) 3.4 - 5 x 0.2

(Subtraction) 3.4 - 1 = 2.4

2.4

I'm always happy to help :)

¿Cuál es el Valor presente neto del nuevo equipo? Una empresa de reciclaje tiene el proyecto de hacer una inversión en equipo relacionado con el triturado de hule. Se pronostica que el nuevo equipo tiene un valor en el mercado de $150 000 y representará para la compañía un ahorro de mano de obra y desperdicio de materiales del orden de $50 000 anuales y al final de los cuales se espera una recuperación monetaria de $ 25,000 ( en el periodo cinco serían 75 000) Se toma en consideración que la vida útil estimada para el nuevo equipo es de 5 años. Se recomienda considerar que la empresa ha fijado una TREMA (tasa de rendimiento mínima aceptable) de 20%.

Answers

Answer:

so I dont understand Spanish sorry I just need the points ㅠㅠ

Can someone plz help me solved this problem I need help plz help me! Will mark you as brainiest!

Answers

Answer:

11

4

Step-by-step explanation:

3 hrs to travel 45 miles downstream

4 hrs to travel 28 miles upstream

speed of boat in still water= s

speed of the current= c

s+c= 45/3= 15s-c= 28/4=7

added up the 2 equations, we get:

2s= 22s= 11 mphc= 4 mph

are all parallelograms quidrilaterals

Answers

Answer:

yes

Step-by-step explanation:

All four sides of a rhombus are congruent. Its properties include that each pair of opposite sides is parallel, also making it a parallelogram. ... All rectangles are parallelograms, but not all parallelograms are rectangles. And all of these shapes are quadrilaterals.

How much pure acid is in 780 milliliters of a 12​% ​solution?

Answers

Answer:

93.6 ml

Step-by-step explanation:

12% of that 780 ml is pure acid:  0.12(780 ml) = 93.6 ml

The amount of pure acid is 93.6 ml.

What is proportion?

Proportion is explained majorly based on ratio and fractions. A fraction, represented in the form of a/b, while ratio a:b, then a proportion states that two ratios are equal. Here, a and b are any two integers. The ratio and proportion are key foundations to understand the various concepts in mathematics as well as in science.

The direct proportion formula says if the quantity y is in direct proportion to quantity x, then we can say y = kx, for a constant k. y = kx is also the general form of the direct proportion equation.

Given:

You have 780 ml of a 12% solution

So,

780 ml represents 100%,

x ml represents 12%.

Using proportion:

780/x= 100/12

780*12/100=x

93.6 ml = x

Learn more about this concept here:

https://brainly.com/question/4867351

#SPJ2

Please answer this correctly

Answers

Answer:

8

Step-by-step explanation:

18(4/3)=24

6(4/3)=h

h=8

Answer:

h = 8

Step-by-step explanation:

These shapes are similar, so you can set up a proportion to solve for h:

[tex]\frac{24}{18}= \frac{h}{6}[/tex]

Cross multiply:

[tex]\frac{144}{18h}[/tex]

Divide 144 by 18:

h = 8

Select the correct answer.
Circle O is represented by the equation (x + 7)2 + (x + 7)2 = 16. What is the length of the radius of circle O?
A. 3
B. 4
C. 7
D. 9
E. 16

Answers

Answer:

4

Step-by-step explanation:

because r2=16 so you have to find the square root of 16 to get r

Which number is the additive inverse of -5?
1
О-5
ОО
ch.
O5

Answers

Answer:

5

Step-by-step explanation:

Additive inverses are two numbers that add to 0.

Since -5 + 5 = 0, then the additive inverse of -5 is 5.

Answer: 5

Answer:

It would just be the opposite -5 the inverse is 5.

Step-by-step explanation:

Hope my answer has helped you in anyway and if not I am sorry.

Mr. Lim and Mr. Tay had $31 090 at first.Mr. Lim donated $2390 of his money and Mr. Tay spent half of his money on a holiday trip. As a result, Mr. Lim had 3 times as much money as Mr. Tay. How much money did Mr. Lim have at first?

Answers

Answer:

Mr.Lim had 19610 dollars, and Mr.Tay had 11480 dollars at first.

Step-by-step explanation:

Mr. Lim had 19610 dollars at first.

To find how much did Mr. Lim had at first.

Given:

Mr. Lim and Mr. Tay had $31 090 at first.

Mr. Lim donated $2390 of his money and

Mr. Tay spent half of his money on a holiday trip.

Mr. Lim had 3 times as much money as Mr. Tay.

Step 1:

Let Mr. Tay had x

Let Mr. Lim had y

x + y=31090………..(1)

Step 2:

Mr. Tay spent on holiday = x + 2390/2

Money left with Mr. Lim = y - 2390

Given,

y - 2390 = 3(x + 2390/2) .............(2)

Step 3:

Equating equation (1) and (2)

we get,

x = 11480

y = 19610

Hence, Mr. Lim has $19610, and Mr. Tay had $11480 dollars at first.

To learn how to calculate the amount spent, refer,

https://brainly.com/question/2263981

#SPJ2

In a certain city, the monthly cost of telephone service is given the function C = 0.10n + 18, where n is the number of calls, 10 cents is the cost per call, and $14 is a fixed charge. Find the cost of making 60 calls a month.

Answers

Answer:

The cost of making 60 calls a month is $20.

Step-by-step explanation:

There was a small typing mistake there. If the fixed charge is $14, the cost of n calls is given by the following equation:

[tex]C(n) = 0.1n + 14[/tex]

Find the cost of making 60 calls a month.

This is C(60), that is, C when n = 60. So

[tex]C(n) = 0.1n + 14[/tex]

[tex]C(60) = 0.1*60 + 14 = 20[/tex]

The cost of making 60 calls a month is $20.

___, ___, 17, ___, ___, 29 Work out the missing terms. Work out the nth term

Answers

Answer:

The sequence is of the form

9 ,   13 , 17 , 21 , 25 ,29

Step-by-step explanation:

Explanation:-

Step(i):-

Given sequence   , ___, __17_ ,___,___ 29

The third term = 17

          a + (3-1)d = 17

          a + 2 d = 17 ...(i)

The sixth term = 29

      a + (6-1)d =29

      a + 5 d  = 29 ...(ii)

solving (i) and (ii) equations

Subtracting (i) and (ii) equations , we get

 a + 2 d -a -5 d = 17 -29

   - 3 d = - 12

       d =4

Substitute 'd' =4 in equation (i)

   a + 2 d = 17

  a + 2(4) =17

  a = 17 -8 = 9

Step(ii):-

The arithmetic sequence

            a ,   a+d ,   a+2 d  ,  a+ 3 d , a+ 4 d , a+5 d

            9  , 9 + 4, 9 +2 (4) , 9+3(4) , 9 +4(4) , 9+5(4)

             9 ,   13 , 17 , 21 , 25 ,29

Conclusion:-

The sequence is of the form

9 ,   13 , 17 , 21 , 25 ,29

   

9, 13, 17, 21, 25, 29

are the values of the expressions 2m−13 and m+3 equal?

Answers

Answer:

The correct answer is m=8

Evaluate-2+7x^2-2x^3-8x+7x^4 at x=5

Answers

Answer:

4262

Step-by-step explanation:

2 + 7x^2- 2x^3-8x +7x^4     at x = 5

= 2 + 7*(5)^2 - 2*(5)^3-8*5 +7*(5)^4

=2+175-250-40+4375

=4552-290

=4262

There are 64 students in a speech contest. Yesterday, Ā of them gave their speeches. Today, 7 of the remaining students gave their speeches. How many
students still haven't given their speeches?
M

Answers

Answer:

23

Step-by-step explanation:

Ā means the average

So it means the average of 64 gave their speech which should be 64/2 = 32

So 32 gave their speeches yesterday,

7 gave today

Total number that has given is

32 + 7 = 39

Therefore the number remaining are

62 - 39 = 23

In the diagram below BD parallel to XY. What is the value of 2

Answers

Answer:69

Step-by-step explanation: Because I am smart

Someone please help me! Ill give the brainlest if its correct! A chemical company makes two brands of antifreeze. The first brand is 45% pure antifreeze, and the second brand is 95% pure antifreeze. In order to obtain 50 gallons of a mixture that contains 80% pure antifreeze, how many gallons of each brand of antifreeze must be used?

Answers

Answer:

therefore x equals 3

Step-by-step explanation:

g(1) = 1² + 1 = 2

Researchers suspect that myopia, or nearsightedness, is becoming more common over time. A study from the year 2010 showed 123 cases of myopia in 400 randomly selected people. Another study from the year 2019 showed 228 cases in 600 randomly selected people. We are going to do a hypothesis test to see if p1 = the proportion of people who have myopia in 2019 is equal to p2 = proportion of people who have myopia in 2010 at the 0.05 significance level.
null and alternative hypothesis ?
a. H0:P1=P2; Ha:P1≥P2
b. H0:P1=P2; Ha:P1≠P2
c. H0:P1≠P2; Ha:P1=P2
d. H0:P1≥P2; Ha:P1≠P2

Answers

Answer:

We want to test if the  if p1 = the proportion of people who have myopia in 2019 is equal to p2 = proportion of people who have myopia in 2010 (alternative hypothesis) , then the system of hypothesis are:

Null hypothesis: [tex]p_1 = p_2[/tex]

Alternative hypothesis: [tex] p_1 = p_2[/tex]

And the best option would be:

b. H0:P1=P2; Ha:P1≠P2

Step-by-step explanation:

For this case we have the following info given:

[tex]X_1 = 228 [/tex] the myopia cases in 2019

[tex] n_1= 600[/tex] the sample size in 2019

[tex] \hat p_1= \frac{228}{600}= 0.38[/tex] estimated proportion of myopia cases in 2019

[tex]X_2 = 123 [/tex] the myopia cases in 2010

[tex] n_2= 400[/tex] the sample size in 2010

[tex] \hat p_2= \frac{123}{400}= 0.3075[/tex] estimated proportion of myopia cases in 2010

And we want to test if the  if p1 = the proportion of people who have myopia in 2019 is equal to p2 = proportion of people who have myopia in 2010 (alternative hypothesis) , then the system of hypothesis are:

Null hypothesis: [tex]p_1 = p_2[/tex]

Alternative hypothesis: [tex] p_1 = p_2[/tex]

And the best option would be:

b. H0:P1=P2; Ha:P1≠P2

And we can conduct a two sample z proportion test in order to verify the hypothesis.

Answer:

< 0.5 \leqslant pvalue < 0.10[/tex]answer C on khan academy

Please answer this correctly

Answers

Answer

51

Explanation

85/15=y/9

765=15y

51

Answer:

y = 51

Step-by-step explanation:

These triangles are similar, so you can set up a proportion to solve for y:

[tex]\frac{85}{15} =\frac{y}{9}[/tex]

Cross multiply:

[tex]\frac{765}{15y}[/tex]

Divide 765 by 15:

y = 51

Two numbers are in the ratio of 3:4. If they sum of the numbers is 63, find the numbers

Answers

Answer:

27 and 36

Step-by-step explanation:

Let's call the two numbers x and y.

[tex]3x=4y \\\\x+y=63[/tex]

If you subtract y from both sides of the second equation, you can isolate x and substitute it into the first equation:

[tex]x=63-y \\\\3(63-y)=4y\\\\189-3y=4y\\\\189=7y\\\\y=27\\\\x=63-27=36[/tex]

Hope this helps!

Five crates weigh 200 pounds. One crate weighs 20 pounds but each of the other four crates weigh the same amount. What is the weight of the other 4 crates?

Answers

Subtract 20 from the total weight and divide by 4:

200 - 20 = 180

180/4 = 45

Each other crate weighs 45 pounds each.

an employee of a grocery store is placing an order for soda. there are 8 varieties of soda and they are sold in cases. each case contains all the same variety of soda. the store will order 50 cases total. how many ways are there to place the order

Answers

Answer:

There are 536,878,650 ways to place the order.

Step-by-step explanation:

The order in which the cases are put is not important. So we use the combinations formula to solve this question.

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:

8 varieties from a set of 50. So

[tex]C_{50,8} = \frac{50!}{8!(50-8)!} = 536878650[/tex]

There are 536,878,650 ways to place the order.

Ivan and Tanya share £150 in the ratio 4:1
Work out how much more Ivan gets compared to Tanya.

Answers

Ivan gets £120 and Tanya gets £30 so the difference is £90

Answer:

Ivan gets £90 more than Tanya.

Step-by-step explanation:

£150÷5=£30

Every 1 part of the ratio is £30

Ivan : Tanya

£120:   £30

Ivan gets £90 more than Tanya.

Which situation shows a constant rate of change? A. The number of play tickets sold compared with the number of minutes before the play starts B. The height of a helicopter over time C. The cost of fabric compared with its length in yards D. The outside temperature compared with the number of glasses of lemonade sold

Answers

Answer:

C - The cost of fabric compared with its length over time.

tg15°=.... Help me please ​

Answers

Answer:

2-sqrt(3)

Step-by-step explanation:

google said

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