A textbook store sold a combined total of 412 chemistry and math textbooks in a week. The number of chemistry textbooks sold was three times the number of math textbooks sold. How many textbooks of each type were sold?

Answer:8

Step-by-step explanation:

Answer:

can you please specify the question i mean is this like

Step-by-step explanation:

let the no. be x

ATQ

3x-7

or

3x= -7

To solve this problem, we can use the formula for probability:

P(event) = number of favorable outcomes / total number of outcomes

First, let's find the total number of outcomes. We are selecting 4 balls from 11 without replacement, so the total number of outcomes is:

11C4 = (11!)/(4!(11-4)!) = 330

where nCr is the number of combinations of n things taken r at a time.

Now let's find the number of favorable outcomes for each part of the problem.

Part 1: Exactly two white balls and two red balls

To find the number of favorable outcomes for this part, we need to select 2 white balls out of 6 and 2 red balls out of 5. The number of ways to do this is:

6C2 * 5C2 = (6!)/(2!(6-2)!) * (5!)/(2!(5-2)!) = 15 * 10 = 150

So the probability of selecting exactly two white balls and two red balls is:

P(2W2R) = 150/330 = 0.45 (rounded to two decimal places)

Part 2: At least two white balls

To find the number of favorable outcomes for this part, we need to consider two cases: selecting 2 white balls and 2 red balls, or selecting 3 white balls and 1 red ball.

The number of ways to select 2 white balls and 2 red balls is the same as the number of favorable outcomes for Part 1, which is 150.

To find the number of ways to select 3 white balls and 1 red ball, we need to select 3 white balls out of 6 and 1 red ball out of 5. The number of ways to do this is:

6C3 * 5C1 = (6!)/(3!(6-3)!) * (5!)/(1!(5-1)!) = 20 * 5 = 100

So the total number of favorable outcomes for selecting at least two white balls is:

150 + 100 = 250

And the probability of selecting at least two white balls is:

P(at least 2W) = 250/330 = 0.76 (rounded to two decimal places)

Answer:

$18.00

Step-by-step explanation:

I rounded the prices to the nearest dollar. Then I added all of them up.

The correct answer is option b. When the homoskedasticity assumption is violated, The beta parameter estimates are biased while the rest of the OLS assumptions are correct.

When the homoskedasticity assumption is violated, the ordinary least squares (OLS) estimator is still consistent but no longer efficient. This means that the estimates of the regression coefficients (beta parameters) are still unbiased, but they have higher variances and covariances.

In other words, the OLS estimator is no longer the best linear unbiased estimator (BLUE) and it may be biased when the errors are heteroscedastic. Therefore, option b is correct.

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When the expression 6y - 7, is evaluated with y = 3 and y = -3, then the values are not same. Thus option 2: False is correct.

What is an expression?

Mathematical expressions consist of at least two numbers or variables, at least one arithmetic operation, and a statement. It's possible to multiply, divide, add, or subtract with this mathematical operation.

The given expression is - 6y - 7

Firstly substitute the value of y = 3 in the expression -

6y - 7

Use the arithmetic operation of multiplication -

6(3) - 7

Use the arithmetic operation of subtraction -

18 - 7

11

Now, substitute the value of y = -3 in the expression -

6y - 7

Use the arithmetic operation of multiplication -

6(-3) - 7

Use the arithmetic operation of subtraction -

-18 - 7

-25

Therefore, the values are not same for y = 3 and  y = -3.

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Answer:

11

Step-by-step explanation:

2+2+1(5)+3+3(6) =11

Answer:

116 / 45

Step-by-step explanation:

To add fractions with unlike denominators, we need to find their common denominator.

One way to do this is by finding the least common multiple (LCM) of the denominators.

The LCM of 3, 5, 9 and 15 is 45.

We then convert each fraction so that its denominator is 45:

1/3 = 15/45

3/5 = 27/45

7/9 = 35/45

13/15 = 39/45

Now we can add the fractions:

15/45 + 27/45 + 35/45 + 39/45

To simplify, we can add the numerators and keep the common denominator:

(15 + 27 + 35 + 39) / 45

Which gives us:

116 / 45

Therefore, the sum of the fractions 1/3 + 3/5 + 7/9 + 13/15 is, 116 / 45.

Answer:

being e tnn 6t FCC CBC ni irdghyy42s nhi it a njugkinsa high by nigh

The answer is not one of the given choices. The correct answer is 73.

To find the total number of individuals who took the quiz, we need to add up the frequency (f) for each score (x) and then take the sum:

5(6) + 4(5) + 3(5) + 2(3) + 1(2) = 30 + 20 + 15 + 6 + 2 = 73

Therefore, the answer is not one of the given choices. The correct answer is 73.

       Frequency distributions are portrayed as frequency tables or charts. Frequency distributions can show either the actual number of observations falling in each range or the percentage of observations. In the latter instance, the distribution is called a relative frequency distribution.

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Answer:

40 miles per hour

Step-by-step explanation:

After 1 hour the car traveled 40 miles, after 4 hours the car traveled 160 miles. 4 x 40 = 160. Therefore 40mph.

Answer:

Step-by-step explanation:

It's given that, The base of a triangle is 1 cm more than the height

Let's assume height of the triangle be x and base of the triangle be 1 + x

Also the area of the triangle is 10 cm².

We know that area of triangle is calculated by,

Putting the values we get ,

\( \frac{1}{2} (1 + x) x = 10 \\ \\ (1 + x)x = 10 \times 2 \\ \\ {x}^{2} + x = 20 \\ \\ {x}^{2} + x - 20 = 0\)

Further solving by factorisation,

\(x^2 + x-20 = 0 \\ \\ x^2 +5x-4x - 20 = 0 \\ \\ x(x+5)-4(x+5)= 0 \\ \\ (x-4) (x+5) = 0 \\ \\ (x-4) = 0 \: or \: (x+5)=0 \\ \\ { \underline{x= 4 \: or \: x = 5 }}\)

Since value can't be negative.

So, x = 4.

Hence, height of triangle x = 4 cm

base of triangle = x + 1

= 4 + 1

= 5 cm

Therefore the Base of traingle will be 5 cm and Height of the triangle will be 4 cm.

Answer:

x = 27.2

Step-by-step explanation:

Apply trigonometric function to solve for x.

Reference angle = 54°

Side length opposite to reference angle = 22

Hypotenuse = x

We would apply SOH:

Sin 54 = Opp/Hyp

Sin 54 = 22/x

x*sin 54 = 22

x = 22/sin 54

x = 27.1934955 ≈ 27.2 (nearest tenth)

9514 1404 393

Answer:

  7.  $10,459.28

  8.  $30,060.93

Step-by-step explanation:

Your table 12-2 will tell you the present-value multiplier of the annual payment for a 10-year annuity due will be ...

  7%: 7.515232

  11%: 6.537048

__

7. The 11% table value will be used with a payment of $1600 to find the present value:

  6.537048 × $1600 = $10,459.28 . . . present value of the annuity due

__

8. The 7% table value will be used with a payment of $4000 to find the present value:

  7.515232 × $4000 = $30,060.93 . . . present value of the annuity due

After solving the function S(t) = 12 + 2 sin [(2π)/(365)t], the amount of sunlight becomes 12 hours for the first time is obtained as option B: t = 365/2.

What is a function?

In mathematics, a function is a unique arrangement of the inputs (also referred to as the domain) and their outputs (sometimes referred to as the codomain), where each input has exactly one output and the output can be linked to its input.

The given function is -

S(t) = 12 + 2 sin [(2π)/(365)t]

Here, t is the number of days after 1st January.

S(t) is the number of hours of sunlight in a particular location.

In order to figure out when the amount of sunlight becomes 12 hours for the first time, substitute the value of S(t) = 12 and solve the function for t -

S(t) = 12 + 2 sin [(2π)/(365)t]

12 = 12 + 2 sin [(2π)/(365)t]

Simplifying the equation to get the result -

0 = 2 sin [(2π)/(365)t]

0 = sin [(2π)/(365)t]

π = (2π)/(365)t

Simplify the equation further -

365π = 2πt

t = 365π/2π

t = 365/2

Therefore, the value for t is obtained as t = 365/2.

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The number of hours of sunlight in a particular location S(t) can be modeled by the function S(t) = 12 + 2 sin [(2π)/(365)t], where t is the number of days after January 1st. (That is, t = 0 means January 1st.) After how many days will there be 12 hours of sunlight for the first time during the year?

365 over 4 days

365 over 2 days

1095 over 4 days

1095 over 2 days

Segment, ray and line are one-dimensional figures.

We need to check from the given options which are one-dimensional figures.

One-dimensional: Only a single measurement is possible for a one-dimensional figure. A line segment drawn on a surface is a one-dimensional object, as it has only length and no width.  

Here, the segment is a one-dimensional figure.

Ray is a one-dimensional figure.

Angle is a two-dimensional figure.

A line is a one-dimensional figure.

The plane is a two-dimensional figure.

A cube is a three-dimensional figure.

Therefore, segment, ray and line are one-dimensional figures.

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Answer:

68% of the data points lie between 10 and 18.

Step-by-step explanation:

one standard deviation to left of mean = 14 - 4 =10

one standard deviation to right of mean = 14 + 4 = 18

68% of data is in this region.

so the answer is 68% of the data points lie between 10 and 18.

Answer:

AOB = 73

BOC = 107

Step-by-step explanation:

So make an equation.

9x + 27 = 180

9x = 153

x = 17

AOB = 73

BOC = 107

Anna's total profit was $6000 + $16000 - $4000 = $14000.

How did Anna earn profit

Anna bought $4000 of company stock. The value of the stock doubled when she sold 75% of it, which means she sold 0.75 * $4000 = $3000 worth of stock when its value doubled.

Since the value of the stock doubled, Anna sold the $3000 worth of stock for 2 * $3000 = $6000.

Anna then sold the remainder of the stock (25% of the original amount) for four times the purchase price. Since she originally bought the stock for $4000, the remainder was worth 0.25 * $4000 = $1000.

Selling this remainder for four times the purchase price means that Anna sold it for 4 * $4000 = $16000.

Answer: x=-9

Step-by-step explanation:

18/x=-2

multiply x

18=-2x

divide by -2

-9=x

x=-9

Answer:

\(18 \div x = - 2 \\ \frac{18}{x} = - 2 \\ x = \frac{18}{ (- 2)} \\ \boxed{x = - 9}\)

Answer:

-18 if youre asking about simple subtraction

Step-by-step explanation:

Answer:

-18

Step-by-step explanation:

its like saying (-45)+27.

you have to add the 27 to 45 to get to 0 and them see how much you have left

Step-by-step explanation:

Find the factors of x that makes it zero.. Equate the equation to y and use it to find the value of y. Then get your values for x and y and plot the graph

Answer:

Jesse with have to wait 4 weeks

Step-by-step explanation:

skip count by 20

Let

x ----> the length side of the base

h ---> is the height of the box

so

The volume of the box is given by the formula

The surface area of the open box is given by the formula

substitute the value of h in the above expression

Find out the first derivative

Equate to zero the first derivative, to calculate the critical point

Find out the second derivative

Evaluate the second derivative for x=20

The value of the second derivative for x=20 is positive

that means

The concavity is up--------> x=20 is a minimum

Find out the value of h for x=20 cm

Find out the surface area for x=20 cm and h=10 cm

Find out the cost

Remember that

The cost of the materials used is $1 per cm^2

so

total cost=1,200(1)=$1,200

therefore

The answer is

Answer:

The first one

Step-by-step explanation:

First, we need to find the experimental probability (probability using the provided data) of landing on purple.

Experimental probability of purple = # of purple / total #

Experimental probability of purple = 2 / 26 = 1 / 13 (simplified)

Next, we need to consider the probability in the context of 13 spins, as per the question. Our experimental probability tells us that 1 out of every 13 spins will be purple. Therefore, we can expect 1 of the next 13 spins to land on purple.

Answer: 1 spin

Hope this helps!

Answer:

28. 120 degrees

29. 30 degrees

30. 56 degrees & 124 degrees

31. 72 degrees, 108 degrees, and 18 degrees

Step-by-step explanation:

We assign variable x for the answer we are looking for (28-29).

28.

Supplement means x + y = 180 degrees. We also know x = 2y. Substitution gives us 3y = 180 degrees, so y = 60 degrees and x = 120 degrees.

29.

Complement means x + y = 90 degrees. We are given 2x = y. Substitution brings us 3x = 90 degrees, x = 30 degrees.

30.

Supplement means x + y = 180 degrees. We are told that y = 2x + 12, so we substitute. This gives 3x + 12 = 180 degrees, x = 56 degrees. Substituting that back into the equation for y, we get 124 degrees.

31.

Supplement means x + y = 180 degrees. Complement means x + z = 90 degrees.  Using our given info, we know y = 6z. We can substitute that in to get x + 6z = 180. Subtracting our second and third equations, we get 5z = 90, z = 18 degrees.  Therefore, x = 72 degrees, y = 108 degrees.