A decision at the margin Crystal is a hard-working college senior. One Thursday, she decides to work nonstop until she has answered 100 practice problems for her math course. She starts work at 8:00 AM and uses a table to keep track of her progress throughout the day. She notices that as she gets tired, it takes her longer to solve each problem. Time Total Problems Answered 8:00 AM 0 9:00 AM 40 10:00 AM 70 11:00 AM 90 Noon 100 Use the table to answer the following questions. The marginal, or additional, gain from Crystal’s first hour of work, from 8:00 AM to 9:00 AM, is problems. The marginal gain from Crystal’s third hour of work, from 10:00 AM to 11:00 AM, is problems. Later, the teaching assistant in Crystal’s math course gives her some advice. “Based on past experience,” the teaching assistant says, “working on 35 problems raises a student’s exam score by about the same amount as reading the textbook for 1 hour.” For simplicity, assume students always cover the same number of pages during each hour they spend reading. Given this information, in order to use her 4 hours of study time to get the best exam score possible, how many hours should she have spent working on problems, and how many should she have spent reading? 0 hours working on problems, 4 hours reading 1 hour working on problems, 3 hours reading 3 hours working on problems, 1 hour reading 4 hours working on problems, 0 hours reading

The value of expression is n=3 and r= 16

An expression is a set of terms combined using the operations +, – , x or , /.

Given:

[tex](4k^{7})^{3} = 4^{n}* (k^{7})^{3} = 64 k^{21}[/tex]

[tex](64 k^{21}) = 4^{n}* k^{21} = 64 k^{21}[/tex]

[tex]4 ^{3} * k^{21}= 4^{n}* k^{21}[/tex]

On comparing

n=3

Now,

[tex](-3r^{-4})^{-4} = (-3)^{-4} * (r^{-4})^{-4} = 1/81* r^{m}[/tex]

[tex](-3)^{-4} * (r^{-4})^{-4} = 1/81* r^{m}\\1/ (-3)^{4} * 1/(r^{-4})^{4} = 1/81* r^{m}\\1/ (-3)^{4} * (r^{16}) = 1/81* r^{m}[/tex]

1/81 * r^16 = 1/81 * r^{m}

On compairing

r = 16.

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Answer:

answer in picture

Step-by-step explanation:

Answer:

1491 girls (99.4 percent)

Step-by-step explanation:

explanation is in the attached picture

Answer:

-7 is -7 units away from zero. Its opposite is 7 from zero.

Step-by-step explanation: Count from 0 how many digits away it is

The y-coordinate of the other endpoint is 10 units.

The given coordinates are H (-5, 2) and G (–9, –6).

We need to find the y-coordinate of the other endpoint.

The mid-point formula is  [tex](x, y)=(\frac{x_{1}+x_{2} }{2} , \frac{y_{1}+y_{2} }{2})[/tex]

Now, [tex](-5, 2)=(\frac{x_{1} +(-9)}{2} , \frac{y_{1} +(-6)}{2})[/tex]

⇒[tex]2=\frac{y_{1}-6 }{2}[/tex]

⇒[tex]4=y_{1}-6[/tex]

⇒[tex]y_{1}=10[/tex]

Therefore, the y-coordinate of the other endpoint is 10 units.

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Answer:

Anita= 25 years old

Sumbo= 10 years old

Step-by-step explanation:

Start by forming 2 equations that represent the given information.

Let Anu's and Sumbo's ages be A and S respectively.

A= S +15 -----(1)

A² +S²= 725 -----(2)

Now, solve for A and S by substitution.

Substitute (1) into (2):

(S +15)² +S²= 725

Expand:

S² +2(S)(15) +15² +S²= 725

2S² +30S +225= 725

-725 on both sides:

2S² +30S -500= 0

Divide both sides by 2:

S² +15S -250= 0

Factorise:

(S +25)(S -10)= 0

S +25= 0             or            S -10= 0

S= -25 (reject)     or            S= 10

Sumbo's age cannot be a negative value hence -25 is rejected.

Substitute S= 10 into (1):

A= S +15

A= 10 +15

A= 25

Answer:

B. 47 7/12

Step-by-step explanation:

=126 1/4 - 78 2/3

Change the two mix fraction to improper fractions.

= 505/4 - 236/3

= 1515-944/12

= 571/12

= 47 7/12

Answer:

Speed of light 186000 miles/second.

it takes 500 seconds (approx 8 minutes) for light from the sun to reach Earth.

Step-by-step explanation:

Earth travels around the sun in a slightly oval-shaped orbit, known as an ellipse. Therefore, the planet's distance from the sun changes throughout the year.

However, the average distance from Earth to the sun is about 93 million miles (150 million kilometres). Scientists also call this distance one astronomical unit (AU).

A universe is a big place, and sometimes researchers use astronomical units to communicate how far celestial objects are separated from one another. For example, Jupiter orbits about 5 AU from the sun.

The distance between the earth and the sun d= velocity of light × time taken to reach light from the sun to earth

Distance from Earth to Sun=93000000 miles.

Speed of light = 186000 miles/second.

=>  [tex]\frac{93000,000}{186000}[/tex]

=> 500 seconds.

=> 8.333 minutes

it takes 500 seconds (approx 8 minutes) for light from the sun to reach Earth.

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Answer:

48 cm²

Explanation:

Let the breadth be b, then the length is 3b

P = 2(Length + Breadth)

32 = 2(3b + b)

32 = 2(4b)

8b = 32

b = 4

Breadth is 4 cm

Length: 3b = 3(4) = 12 cm

Area of rectangle:

Length × Breadth

12 × 4

48 cm²

Given :-

To Find :-

Solution :-

Using formula;

Where;

We have;

By putting all values in formula we get;

→ 2(3x + x) = 32

→ 2(4x) = 32

→ 2 × 4x = 32

→ 8x = 32

→ x = 32/8

After dividing 32 with 8, we get;

→ x = 4

Hence;

Now, using formula;

Where;

We have;

By putting all values in formula we get;

→ Area of rectangle = 12 × 4

By multiplying 12 with 4, we get;

→ Area of rectangle = 48 cm²

Answer:

36 seconds will be the answer... by looking down here↓:

Step-by-step explanation:

6 secs x 6 cycles = 36 seconds

9 secs x 4 cycles = 36 secs

12 ses x 3 cycles = 36 secs

Answer: 180 degrees

Step-by-step explanation:

The measure of the arc of a semicircle is 180 degrees.

Answer:

3x^2 + 3xz

Step-by-step explanation:

Under the assumption that I need to distribute,

(x + z)(x + 2x)

(x + 2x) is (3x)

3x(x + z) becomes 3x*x and 3x*z

3x*x = 3x^2

3x*z = 3xz

combine, 3x^2 + 3xz

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The answer is simple

First find the angle measures of first triangle:

statement:

we know that the sum of 45 and 30 sums up to the opposite angle and that is equal to 75, then to find the next remaining angle:

180-(75+20)=85

The you find the supplement of 85:

180-85=95

so x = 95

Hope it helps

The quotient [tex]\frac{x^2 - 49}{x + 2} \div \frac{x^2 - 14 +49}{3x + 6}[/tex] is [tex]\frac{3(x +7)}{(x -7)}[/tex]

The expression is given as:

[tex]\frac{x^2 - 49}{x + 2} \div \frac{x^2 - 14 +49}{3x + 6}[/tex]

Express x^2 - 49 as difference of two squares

[tex]\frac{(x + 7)(x- 7)}{x + 2} \div \frac{x^2 - 14 +49}{3x + 6}[/tex]

Factorize other expressions

[tex]\frac{(x + 7)(x- 7)}{x + 2} \div \frac{(x -7)(x-7)}{3(x + 2)}[/tex]

Express as product

[tex]\frac{(x + 7)(x- 7)}{x + 2} \times\frac{3(x + 2)}{(x -7)(x-7)}[/tex]

Cancel the common factors

[tex]\frac{(x + 7)}{1} \times\frac{3}{(x -7)}[/tex]

Evaluate the product

[tex]\frac{3(x +7)}{(x -7)}[/tex]

Hence, the quotient [tex]\frac{x^2 - 49}{x + 2} \div \frac{x^2 - 14 +49}{3x + 6}[/tex] is [tex]\frac{3(x +7)}{(x -7)}[/tex]

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The number of the meals possible is 350.

The complete question is given below:-

A menu has 5 choices of appetizers, ten main courses, and seven desserts. How many meals are possible?

The arrangement of the different things or numbers in a number of ways is called the combination.

Given that:-

The number of the combination of the meals will be calculated as:-

N = 5 x 10 x 7

N = 350

Therefore the number of the meals possible is 350.

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The proportion of sides of the triangle which is not true are 13.5/21 = 9/14, 9/13.5 = 6/21 and 14/6 = 21/9

The three sides of each of the rectangles should be proportional to each other

Triangle A : Triangle B

9 cm : 13.5 cm

= 9/13.5

14 cm : 21 cm

= 14 cm / 21 cm

6 cm : 9 cm

= 6 cm / 9 cm

Therefore, the proportion of sides of the triangle which is not true are 13.5/21 = 9/14, 9/13.5 = 6/21 and 14/6 = 21/9

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Answer:

[tex]x = \frac{25}{13} [/tex]

Step-by-step explanation:

Given:

[tex] \frac{2}{5} x - \frac{1}{2} = \frac{1}{3} + \frac{5}{6} x[/tex]

Combine like terms:

[tex] \frac{2}{5} x - \frac{5}{6} x = \frac{1}{3} + \frac{1}{2} [/tex]

Find GCF :

[tex] \frac{12}{30} x - \frac{25}{30} = \frac{2}{6} + \frac{3}{6} [/tex]

Subtraction and Addition :

[tex] \frac{13}{30} x = \frac{5}{6} [/tex]

Divide both sides by 13/30 :

[tex] \frac{ \frac{13}{30} }{ \frac{13}{30} } x = \frac{ \frac{5}{6} }{ \frac{13}{30} } [/tex]

Simplify :

Multiplication (Reciprocal) :

[tex]x = \frac{5}{6} \times \frac{30}{13} [/tex]

[tex]x = \frac{150}{78} [/tex]

[tex]x = \frac{25}{13} [/tex]

Answer :

[tex]x = \frac{25}{13} [/tex]

Hope it helps

Step-by-step explanation:

I'm going to assume you meant to write [tex]\sqrt{r+1}[/tex] in the equation as +1 - 1 wouldn't make much sense since they would just cancel out.

a. [tex]f(-1) = \sqrt{-1 + 1} - 1\\ f(-1) = \sqrt{0} - 1\\f(-1) = 0-1\\f(-1) = -1[/tex]

b. [tex]f(24) = \sqrt{24 + 1} - 1\\ f(24) = \sqrt{25} - 1\\f(24) = 5 - 1\\f(24) = 4[/tex]

c. [tex]f(x-1) = \sqrt{(x-1)+1} -1\\f(x-1) = \sqrt{x} - 1[/tex]

Answer:

C   34  cm

Step-by-step explanation:

Area = L x W

  72  = 8 x W     then W = 9

Perimeter = 2 ( L+W) = 2 ( 8+ 9) = 34  cm

[tex]\huge\text{Hey there!}[/tex]

[tex]\large\text{Area of rectangle: A = wl; whereas \boxed{\textsf a} is \underline{area}, \boxed{\textsf w} is \underline{width}, \& \boxed{\textsf{l}} is}\\\large\text{\underline{length}.}[/tex]

[tex]\large\text{a = wl}\\\\\large\text{wl = a}\\\\\large\text{w(8) = 72}\\\\\large\text{8w = 72}\\\\\large\textsf{DIVIDE 8 to BOTH SIDES}\\\\\rm{\dfrac{8w}{8} = \dfrac{72}{8}}\\\\\large\text{SIMPLIFY IT!}\\\\\rm{w = \dfrac{72}{8}}\\\\\rm{w = 9}\\\\\\\huge\text{Therefore, your answer should be: \boxed{\mathsf{width = \bf 9}}}\huge\checkmark[/tex]

[tex]\huge\text{Good luck on your assignment \& enjoy your day!}[/tex]

~[tex]\frak{Amphitrite1040:)}[/tex]

27

Solution:

21 + ( -3 ) ( -2 )

21 + 6

27

Therefore, The answer is 27.

Answer: [tex]\left(\frac{1}{2}, 1 \right), (1, 2)[/tex]

Step-by-step explanation:

We have [tex]y=2x^{2}[/tex] and [tex]y=3x-1[/tex].

Since both of the equations are set equal to y, we can conclude that:

[tex]2x^2 = 3x-1\\\\2x^{2}-3x+1=0\\\\(2x-1)(x-1)=0\\\\x=\frac{1}{2}, 1[/tex]

If [tex]x=\frac{1}{2}[/tex], then [tex]y=3\left(\frac{1}{2} \right)-1=1[/tex]

If [tex]x=1[/tex], then [tex]y=3-1=2[/tex]

Therefore, the solutions are [tex]\left(\frac{1}{2}, 1 \right), (1, 2)[/tex]

The missing pattern behind the sequence 7, 11, 2, 18, -7 is described by the formula [tex]n = 7 + \sum \limits_{i= 1}^{n} (-1)^{i+1}\cdot (i + 1)^{2}[/tex], equivalent to the recurrence formula [tex]a_{n+1} = a_{n} + (-1)^{i+1}\cdot (i + 1)^{2}[/tex].

A sequence is a set of elements which observes at least a defined rule. In this question we see a sequence which follows this rule:

[tex]n = 7 + \sum \limits_{i= 1}^{n} (-1)^{i+1}\cdot (i + 1)^{2}[/tex]      (1)

Now we prove that given expression contains the pattern:

n = 0

7

n = 1

7 + (- 1)² · 2² = 7 + 4 = 11

n = 2

7 + (- 1)² · 2² + (- 1)³ · 3² = 11 - 9 = 2

n = 3

7 + (- 1)² · 2² + (- 1)³ · 3² + (- 1)⁴ · 4² = 2 + 16 = 18

n = 4

7 + (- 1)² · 2² + (- 1)³ · 3² + (- 1)⁴ · 4² + (- 1)⁵ · 5² = 18 - 25 = - 7

The missing pattern behind the sequence 7, 11, 2, 18, -7 is described by the formula [tex]n = 7 + \sum \limits_{i= 1}^{n} (-1)^{i+1}\cdot (i + 1)^{2}[/tex], equivalent to the recurrence formula [tex]a_{n+1} = a_{n} + (-1)^{i+1}\cdot (i + 1)^{2}[/tex].

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The three consecutive integers are 15 16 and 17.

Step 1:

Let  X be the first integer. Since they are consecutive, it means that the second number will be X + 1 and the third number will be X + 2 and sum of the first and the third should add up to 32. Therefore, you can write the equation as follows:

(X) + (X + 1) + (X + 2) be the three consecutive integers.

Step 2:

The sum of the first and the third should add up to 32.

X + ( X + 2 )= 32

2X + 2= 32

2X = 32 - 2

2X = 30

X = 30/2

X=15

Hence the first number is 15, the second number is 15 + 1, and the third number is 15 + 2.

Therefore, three consecutive integers in which the sum of the first and the third is 32 are 15 16, and 17.

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(a) [tex]\{x: x > -4 \}[/tex]

(b) [tex](-4, \infty)[/tex]

Answer:

eyyyyyyyyyy wassupppppppp

Answer:

240%

Step-by-step explanation:

Volume of a prism is Bh (area of the base * height)

Let's start with the small prism.

B=125

h=12

Volume = 125*12 = 1500 cubic cm

Bigger prism base are is 160% of 125. 1.6 * 125 = 200

Height is 6 cm more = 12+6 = 18

V = 200 * 18 = 3600

To find the percentage, divide 3600 by 1500. You get 2.4, which is 240%

Answer:

the answer is B. 140 units²

The reflection is

A reflection of a point, a line, or a figure in the X axis involved reflecting the image over the x axis to create a mirror image. In this case, the x axis would be called the axis of reflection.

For reflecting over the X axis is to negate the value of the y-coordinate of each point, but leave the x-value the same.

and, for reflecting over the Y axis is to negate the value of the x-coordinate of each point, but leave the y value the same.

So, by considering the above value rules the reflection of the given points as follows over respective axis.

E(7, 1) ⇒ (7, -1)

Here, the reflection is over x-axis because the y value is changing

F(-3, 5) ⇒ (-3, -5)

Here, the reflection is over x-axis because the y value is changing

G(6, -2) ⇒ (-6, -2)

Here, the reflection is over y-axis because the x value is changing.

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The expression written in equivalent form with a common denominator is -1/6

Fractions are written as ratio of two integers. For instance a/b is a fraction.

Given the sum of the fractions shown;

-3/4 and 5/8

Sum = -3/4 + 5/8

Sum = 5/8 - 3/4

Sum = 5-6/8

Sum  = -1/8

Hence the sum of the given fraction -1/3 and 5/8 is -1/6

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There are 210 different three-digit whole numbers that can be formed with the digits 2, 3, 4, 5, 6, 7, 8 if the digits cannot be repeated.

To calculate how many different three-digit whole numbers can be formed with the digits 2, 3, 4, 5, 6, 7, 8 if the digits cannot be repeated, we need to use the permutation formula.

The number of permutations of n objects taken r at a time, where order matters and objects cannot be repeated, is given by:

P(n,r) = n! / (n-r)!

In this case, we have 7 digits to choose from, and we want to form a three-digit number, so r = 3. Therefore, the number of different three-digit whole numbers that can be formed is:

P(7,3) = 7! / (7-3)! = 7! / 4! = 7 x 6 x 5 = 210

Each of these numbers will be unique, as we are not allowed to repeat any of the digits.

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Answer:

D. Sqroot6

Step-by-step explanation:

6 is not a perfect square. So it is a non-repeating decimal that never ends

sqroot6 ~=

2.4494897428...

this is an irrational number.

The rest on the numbers can be written as a ratio:

0.45=45/100=9/20

0.63636363

= 63/99 = 7/11

sqrt25 = 5 = 5/1

that means they are rational.