Math 120 - 01 Summer 2021
Consuelo Butler
08/07
Homework: Practice
Exam 3
Question 1, 12.1.13
HW Score: 10%, 3 of 30 points
Score: 1 of 1
A professor had students keep track of their social interactions for a week. The
number of social interactions over the week is shown in the following grouped
frequency distribution. How many students had at least 60 social interactions for
the week?
12
Number of Social
Interactions
30-34
35-39
40-44
45-49
50-54
55-59
60-64
65-69
70-74
75-79
Frequency
9
14
11
15
16
8
7
3
1
1

Step-by-step explanation:

a. The mean can be found using the AVERAGE() function.

x = 272.7

b. The standard deviation can be found with the STDEV() function.

s = 39.9

c. The t-score can be found with the T.INV.2T() function.  The confidence level is 0.04, and the degrees of freedom is 26.

t = 2.162

d. Find the lower and upper ends of the confidence interval.

Lower = 272.7 − 2.162 × 39.9 = 186.5

Upper = 272.7 + 2.162 × 39.9 = 358.9

Answer:

  C.  -1

  D.  1

Step-by-step explanation:

A perfect linear relationship is indicated by a correlation with a magnitude of 1. The sign of the correlation coefficient is the sign of the slope of the line describing the relationship. It may be positive or negative.

The appropriate choices are ...

  C.  -1

  D.  1

Answer:

c=-1

d=1

Step-by-step explanation:

Answer: The multiplicative inverse of – 1 in the set {-1,1} is -1.

Step-by-step explanation:

In algebra, the multiplicative inverse of a number(x) is a number (say y) such that

[tex]x\times y=1[/tex]  [product of a number and its inverse =1]

if x= -1, then

[tex]-1\times y=1\Rightarrow\ y=-1[/tex]

That means , the multiplicative inverse of -1 is -1 itself.

Hence, the multiplicative inverse of – 1 in the set {-1,1} is -1.

Answer:

C

Step-by-step explanation:

An arithmetic sequence has a common difference d between consecutive terms.

Sequence a

30 - 10 = 20

90 - 30 = 60

270 - 90 = 180

This sequence is not arithmetic

Sequence b

200 - 100 = 100

300 - 200 = 100

400 - 300 = 100

This sequence is arithmetic but is finite, that is last term is 400

Sequence c

300 - 150 = 150

450 - 300 = 150

600 - 450 = 150

This sequence is arithmetic and infinite, indicated by ........ within set

Sequence d

2 - 1 = 1

4 - 2 = 2

8 - 4 = 4

This sequence is not arithmetic

Thus the infinite arithmetic sequence is sequence c

Answer:

1/254,251,200 Or 0.000000003933118

Step-by-step explanation:

1/50x1/49x1/48x1/47x1/46=1/254,251,200

Let breadth be x

Length=5x

ATQ

[tex]\\ \sf \longmapsto Area=Length\times breadth[/tex]

[tex]\\ \sf \longmapsto 5x(x)=180[/tex]

[tex]\\ \sf \longmapsto 5x^2=180[/tex]

[tex]\\ \sf \longmapsto x^2=\dfrac{180}{5}[/tex]

[tex]\\ \sf \longmapsto x^2=36[/tex]

[tex]\\ \sf \longmapsto x=\sqrt{36}[/tex]

[tex]\\ \sf \longmapsto x=6in[/tex]

Answer:

The sum is represented by the polynomial:

[tex]5\,x^9+2 \,x^7+13\,x+4[/tex]

Step-by-step explanation:

Recall that polynomials are added by combining like terms. The only like terms in this addition are: 5 x and 8 x  which added render: 13 x. therefore, the addition of these polynomials renders;

[tex]5\,x^9+2 \,x^7+13\,x+4[/tex]

Answer:

no of new computers sold : 8

no. of refurbished computer sold : 12

Step-by-step explanation:

Let the no. of new computers sold be x

let the no. of refurbished computers sold be y

Given

In March, the store sold 20 computers

x + y = 20

y = 20-x ----- equation 2

selling price of new computer = $500

selling price of x new computer = 500*x = 500x

selling price of refurbished computer = $200

selling price of y refurbished computer = 200*y = 200y

Total selling price of x new computer and y refurbished computers = 500x+200y

given that

total prioce of computer is $6400

thus

500x+200y = 6400

using y = 20-x  from equation 2

500x+200(20-x) = 6400

=> 500x+ 4000 - 200x = 6400

=> 300x = 6400 - 4000 = 2400

=> x = 2400/300 = 8

Thus,

no of new computers sold = 8

no. of refurbished computer sold = 20 -8 = 12

Answer:

7.15 miles

Step-by-step explanation:

4/5 of a mile is equivalent to .8 miles.

32.95

-25.8

7.15

Answer:

Step-by-step explanation:

39.95 - 25.80 = 7.15 miles

Answer:

the answer is

Step-by-step explanation:

1089 first divide then multiply both numbers after that substract the numbers

Answer:

the answer is error

hope it helps

Answer:

21%

Step-by-step explanation:

Percentage reduction is (999.99-789.99)/(999.99)=21%

Complete Question

In a genetics experiment on​ peas, one sample of offspring contained 372 green peas and 35 yellow peas. Based on those​ results, estimate the probability of getting an offspring pea that is green. Is the result reasonably close to the value of 3/4 that was​ expected?

Answer:

The  probability is  [tex]P(g) = 0.9140[/tex]

No it is not close to the probability expected

Step-by-step explanation:

From the question we are told that

    The sample size is  [tex]n = 372 + 35= 407[/tex]

      The  number of  green peas is  [tex]n_g = 372[/tex]

    The  number of  yellow  peas is  [tex]n_y = 35[/tex]

The  probability of getting an offspring pea that is green is mathematically represented as

         [tex]P(g) = \frac{n_g}{n}[/tex]

substituting values

         [tex]P(g) = \frac{372}{ 407}[/tex]

         [tex]P(g) = 0.9140[/tex]

The  expected probability is  [tex]\frac{3}{4} = 0.75[/tex]

But what we got is  [tex]P(g) = 0.9140[/tex]

So we can say that the value obtained is not equal to the expected value

Answer:

No, the owners are not having their transmissions serviced at 30,000 miles.

Step-by-step explanation:

We are given that a car dealer recommends that transmissions be serviced at 30,000 miles.

The car dealer selects a random sample of 40 customers and finds that the average mileage of the automobiles serviced is 30,456. The standard deviation of the population is 1684 miles.

Let [tex]\mu[/tex] = true average mileage of the automobiles serviced.

So, Null Hypothesis, [tex]H_0[/tex] : [tex]\mu[/tex] = 30,000 miles      {means that the owners are having their transmissions serviced at 30,000 miles}

Alternate Hypothesis, [tex]H_A[/tex] : [tex]\mu\neq[/tex] 30,000 miles      {means that the owners are having their transmissions serviced at different than 30,000 miles}

The test statistics that will be used here is One-sample z-test statistics because we know about population standard deviation;

                             T.S.  =  [tex]\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }[/tex]  ~  N(0,1)

where, [tex]\bar X[/tex] = sample average mileage serviced = 30,456 miles  

            [tex]\sigma[/tex] = population standard deviation = 1684 miles

            n = sample of customers = 40

So, the test statistics =  [tex]\frac{30,456-30,000}{\frac{1684}{\sqrt{40} } }[/tex]  

                                     =  1.71

The value of z-statistics is 1.71.

Also, the P-value of the test statistics is given by;

                    P-value = P(Z > 1.71) = 1 - P(Z [tex]\leq[/tex] 1.71)

                                  = 1 - 0.9564 = 0.0436

For the two-tailed test, the P-value is calculated as = 2 [tex]\times[/tex] 0.0436 = 0.0872.

Since the P-value of our test statistics is less than the level of significance as 0.0872 < 0.10, so we have sufficient evidence to reject our null hypothesis as the test statistics will fall in the rejection region.

Therefore, we conclude that the owners are having their transmissions serviced at different than 30,000 miles.

Answer:

x = 450

510/170 = 3

x/150 = 3

x = 450

Answer:

X=450 is the answer.

Step-by-step explanation:

Answer:

a) y = 4

b) RS = 26, ST = 19, RT = 45

Step-by-step explanation:

From the line given, the following vector equation is true, RS + ST = RT since R, S and T lies in the same straight line.

Given RS = 6y + 2, ST = 3y + 7, and RT = 14y - 11

On substituting this values into the equation above we will have;

6y+2+(3y+7) = 14y-11

6y+2+3y+7 = 14y-11

Collect the like terms

6y+3y-14y = -11-7-2

9y-14y = -20

-5y = -20

y = 20/5

y = 4

Since RS = 6y + 2

RS = 6(4)+2

RS = 24+2

RS = 26

ST = 3y + 7

ST = 3(4)+7

ST = 12+7

ST = 19

Also, RT = 14y - 11

RT = 14(4)-11

RT = 56-11

RT = 45

Answer:

The LCM of two numbers is the least common multiple. You want to find the least possible number that is divisible by the two numbers. So, you can list the factors of the two numbers. If there are factors that are repeated, put the repeated factors to the side. With the remaining factors, multiply the factors by each other and the repeated factors.

For example, let's try to find the least common multiple between 10 and 15.

Factors of 10: 2 * 5

Factors of 15: 3 * 5

The repeated factor is 5.

2 and 3 are left over. 2 * 3 = 6. 6 * 5 = 30. So, that is the least common multiple.

The GCF of two numbers is the greatest common factor. You want to find the greatest factor that is included in both numbers. So, again, you can list the factors of the two numbers and find the greatest factor that is repeated between the two numbers.

For example, let's try to find the greatest common factor between 30 and 45.

Factors of 30: 1, 2, 3, 5, 6, 10, 15, 30

Factors of 45: 1, 3, 5, 9, 15, 45

Between the two numbers, shared factors are 1, 3, 5, and 15. So, the greatest common factor is 15.

Hope this helps!

Answer:

$24

Step-by-step explanation:

You simply do $42-$18

=24

Answer:

$24

Step-by-step explanation:

At the start, Jaime had $42. In order to find out how much the T-shirt he purchased costs, we must subtract 18 from 42.

42 - 18 = 24

Jaime spent $24 on the T-shirt.

==================================================

Explanation:

Dividing the side lengths, the scale factor is 6/3 = 2. This means the larger figure has a side length twice as long compared to its smaller counterpart.

How can we use this to figure out how the areas are connected? By simply squaring the scale factor to get 2^2 = 2*2 = 4, then we divide the larger area over 4 to get 24/4 = 6.

The longer side is 2 times longer

The larger area is 4 times larger

--------------------

Let's say we had a 3 by 3 square. It's area would be 9.

Also, let's say we had a 6 by 6 square. It's area is 36.

Notice the ratio of areas is 36/9 = 4, so the larger square is 4 times larger than the smaller. This 4 matches with what we got earlier.

----------------------

Another example:

square A is 7 by 7 with area 49

square B is 21 by 21 with area 441

ratio of areas is 441/49 = 9, which is exactly equal to 3^2, and the 3 comes from the ratio of the sides 21/7 = 3.

------------------------

So in short, you find the linear scale factor by dividing the sides. Then you square the result to get the area scale factor, which you use to find the smaller area.

linear scale factor = (new side)/(old side)

area scale factor = (linear scale factor)^2

smaller area = (larger area)/(area scale factor)

Answer:

B.  P(A|B) = P(A).

Step-by-step explanation:

Question

If a and b are independent events then it must be true that P(A|B)=P(A). TRUE OR FALSE.

Answer

The correct answer is:True.Explanation:P(A|B) is read as “the probability of A given B.” If A and B are independent, this means that B has no effect on A. This means the probability of A given B would be the same as the probability of A, since B has no effect.This means that P(A|B) = P(A).

Answer:

B. P(A|B) = P(A)

Step-by-step explanation:

I got it right on edge 2023 :)

Answer:

(-1,4)

Step-by-step explanation:

The interval in which the function is decreasing is (-1, 4)

Answer:

The domain of a function is the set of all possible inputs for the function.

Using the table provided, the set of all possible inputs is the interval [-6 ; 4].

The range of a function is the complete set of all possible resulting values of the dependent variable (y, usually), after we have substituted the domain. In plain English, the definition means: The range is the resulting y-values we get after substituting all the possible x-values.

Using the table provided, the range is estimated on the interval [-10;20]

The y-intercept is the value on the Y-axis where the function crosses the Y-axis.

Using the table provided, the function crosses the Y-axis for f(0)=18 so for the value y = 18 in the table.

The x-intercept is the value on the X-axis where the function crosses the X-axis.

It happens twice, for f(-6)=0 and f(3)=0.

We estimate the Maximum to be 20, and the Minimum -10.

The function is positive over the interval [-6, 3], and negative over (3;4]

The function is decreasing approximately at f(-1)=20 so at the estimated interval (-1;4]

Answer:

It is still 2 to 7

Step-by-step explanation:

It is still 2 to 7 because if you triple the recipe, it will become 6 to 21 which still simplifies to 2 to 7.

Answer:

v(m) = 8 + 48m+ 180m² +216m³

Step-by-step explanation:

Let's first of all represent the edge of the the cube as a function of minutes.

Initially the egde= 2feet

As times elapsed , it increases at the rate of 6 feet per min, that is, for every minute ,there is a 6 feet increase.

Let the the egde be x

X = 2 + 6(m)

Where m represent the minutes elapsed.

So we Al know that the volume of an edge = edge³

but egde = x

V(m) = x³

but x= 2+6(m)

V(m) = (2+6m)³

v(m) = 8 + 48m+ 180m² +216m³

The volume of cube as function of m is,   [tex]V(m)=72m[/tex]

Let us consider that edge of cube is a feet.

Since,   The edge is increasing at the rate of 6 feet per minute.

                      [tex]\frac{da}{dt}=6feet/min.[/tex]

Volume of cube , V = [tex]a^{3}[/tex]

            [tex]\frac{dV}{dt} =3a^{2} \frac{da}{dt}[/tex]

Substituting the value of  da/dt in above equation.

We get,     [tex]\frac{dV}{dt}=3a^{2}*(6) =18a^{2} \\\\dV=18a^{2}dt[/tex]

Integrating on both side.

          [tex]V=18a^{2}t[/tex]

Since, number of minutes elapsed is m.

Substitute , t = m and a = 2 feet in above equation.

We get,     [tex]V=18(2)^{2}*m=72m[/tex]

Thus, the volume of cube as function of m is,   [tex]V(m)=72m[/tex]

Learn more:

https://brainly.com/question/14002029

Answer:

1, 165.500

Step-by-step explanation:

1, 165.492 rounded to the nearest hundredth is 1, 165.500 because the hundredth space in the decimal is 5 or above, so the whole decimal gets rounded to the nearest hundred, which in this case, would be .500.

165.492 is the correct answer

Answer:

248.26 cm²

Step-by-step explanation:

Surface area of the composite figure = (surface area of cuboid + surface area of hemisphere) - 2(base area of hemisphere)

Surface area of cuboid = [tex] 2(lw + lh + hw) [/tex]

Where,

l = 10 cm

w = 5 cm

h = 4 cm

Plug in the values into the formula:

[tex] SA = 2(10*5 + 10*4 + 4*5) [/tex]

[tex] SA = 2(50 + 40 + 20) [/tex]

[tex] SA = 2(110) = 220 cm^2 [/tex]

Surface area of hemisphere = 3πr²

Where,

π = 3.14

r = 3 cm

SA of hemisphere = 3*3.14*3² = 3*3.14*9 = 84.78 cm²

Base area of hemisphere = πr²

BA = 3.14*3² = 3.14*9 = 28.26 cm²

Surface area of the composite shape = (220 + 84.78) - 2(28.26)

= 304.78 - 56.52

SA = 248.26 cm²

Answer:

Hello,

Answer C

Step-by-step explanation:

Since ln(1)=0

if x=1 then y=4 ==> y=ln(x)+4

y=ln(x) is translated up for 4 units.

Answer:

Garden: 36 square feet

Path: 64 square feet

Step-by-step explanation:

Let's first find the total area. The total area will be 100 square feet since the side length is 10. Since the path is 2 feet wide and on all sides, that means that the inside square will have a side length of 6. That means that the vegetable garden is 36 square feet. The path will be 100 - (the garden), and the garden is 36 square feet, which means the outer path will be 64.

Answer:

0

Step-by-step explanation:

for y= -2*(3^x), as x is greater, the slope is steeper, and since the two graphs don't intercept in the picture we can see, they won't ever intercept because the slop of y=-2x+3 stays the same. as x becomes greater the distance between the two graphs is larger

Answer:

8

Step-by-step explanation:

f(n)= 6-2n

f(-1) = 6- 2(-1)

= 6+2

=8

Answer:

Step-by-step explanation:

Let the equation of a polynomial is,

[tex]y=(x-a)^2(x-b)^1(x-c)^3[/tex]

Zeroes of this polynomial are x = a, b and c.

For the root x = a, multiplicity of the root 'a' is 2 [given as the power of (x - a)]

Similarly, multiplicity of the roots b and c are 1 and 3.

Effect of multiplicity on the graph,

If the multiplicity of a root is even then the graph will touch the x-axis and if it is odd, graph will cross the x-axis.

Therefore, graph will cross x -axis at x = b and c while it will touch the x-axis for x = a.

In this question,

The given polynomial is,

[tex]y=(x-1)^3(x-2)^1(x-4)^1(x-6)^4[/tex]

Degree of the polynomial = 3 + 1 + 1 + 4 = 9

The graph of the function will cross through the x-axis at x = 1, 2, 4 only, The graph will touch to the x-axis at 6 only.

At the zero of 2 , the graph of the function will CROSS the x-axis.