There are 28 students in a class.
13 of the students are boys.
Two students from the class are chosen at random.
a) If the first person chosen is a boy, what is the probability that
the second person chosen is also a boy?
Give your answer as a fraction.
b) What is the probability that both students chosen are girls?
Give your answer as a fraction.

Answer:

Step-by-step explanation:

If the product of two rational numbers is 4/25, we can write the equation:

(x) * (-6/5) = 4/25

where x is the other number.

Expanding the equation:

x * -6/5 = 4/25

Multiplying both sides by 5 to get rid of the fraction on the right-hand side:

5 * x * -6/5 = 5 * 4/25

x * -6 = 4

Dividing both sides by -6:

x = -4/-6

x = 4/6

So, the other number is 4/6.

Answer:

So the other number is -[tex]\frac{4}{3}[/tex].

Step-by-step explanation:

Let x be the number.

We know,

(-[tex]\frac{6}{5}[/tex]) × x = [tex]\frac{4}{25}[/tex]

-[tex]\frac{6}{5}[/tex] × x =  [tex]\frac{4}{25}[/tex]          (By expanding the left side of the equation)

Dividing both sides by -[tex]\frac{6}{5}[/tex]

x = - [tex]\frac{4}{25}[/tex]  × -[tex]\frac{6}{5}[/tex]

After simplifying the equation ,

x = -[tex]\frac{4}{3}[/tex]

So the number is -[tex]\frac{4}{3}[/tex].

Answer:

D.  3√5

Step-by-step explanation:

The distance between points F and C is the hypotenuse of a right triangle.   Therefore we can use Pythagoras Theorem to calculate the distance between these points.

From inspection of the given graph the coordinates of the two points are:

The horizontal difference between the x-coordinates is:

[tex]x_C-x_F=2-(-4)=6\; \sf units[/tex]

The vertical difference between the y-coordinates:

[tex]y_C-y_F=2-(-1)=3\; \sf units[/tex]

Therefore, we have a right triangle with the following dimensions:

[tex]\boxed{\begin{minipage}{9 cm}\underline{Pythagoras Theorem} \\\\$a^2+b^2=c^2$\\\\where:\\ \phantom{ww}$\bullet$ $a$ and $b$ are the legs of the right triangle. \\ \phantom{ww}$\bullet$ $c$ is the hypotenuse (longest side) of the right triangle.\\\end{minipage}}[/tex]

To calculate the length of the hypotenuse, and therefore the distance between points C and F, substitute the values into the Pythagoras Theorem formula and solve for CF:

[tex]\implies a^2+b^2=c^2[/tex]

[tex]\implies 3^2+6^2=CF^2[/tex]

[tex]\implies 9+36=CF^2[/tex]

[tex]\implies CF^2=45[/tex]

[tex]\implies \sqrt{CF^2}=\sqrt{45}[/tex]

[tex]\implies CF=\sqrt{9 \cdot 5}[/tex]

[tex]\implies CF=\sqrt{9} \sqrt{5}[/tex]

[tex]\implies CF=3\sqrt{5}[/tex]

Therefore, the distance between points F and C is 3√5.

Answer:

Step-by-step explanation:

so 1in is 2.5ft.

6.4 times 2.5 is 16.

4.8 times 2.5 is 12.

16+16+12+12

is 24+32.

which is 56.

answer: B

Greta feeds Lizzy 56 crickets when she feeds Draco 77.

Proportion, in general is referred to as a part, share or number considered in comparative relation to a whole.

According to proportion, if two sets of given numbers are increasing or decreasing in the same ratio, then the ratios are said to be directly proportional to each other.

The ratio is a way of comparing two quantities of the same kind by using division. The ratio formula for two numbers a and b is given by a: b or a/b

Given:

For every 11 crickets Greta feeds Draco, she always feeds Lizzy 8 crickets.

Let solve it by an equality

[tex]\frac{11}{8} = \frac{77}{x}[/tex]

We want to solve for x.

We can do so by finding how much larger the second fraction is than the first.

In this case, 77 is 7 times larger than 11.(77/11 = 7)

So, we know that x must be 7 times larger then 8( because the fractions are proportinal)

Since x is 7 times larger than 8, we can use 7 times 8 to find the value.

7 times 8 i s56

56 crickets for Lizzy.

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x is 7 times larger than 8, we can use 7 times 8 to find the value, 7 times 8 is 56. Greta feeds Lizzy 56 crickets while she feeds Draco 77.

What is the Proportion?

Proportion, in general, is referred to as a part, share, or number considered in comparative relation to a whole.

According to proportion, if two sets of given numbers are increasing or decreasing in the same ratio, then the ratios are said to be directly proportional to each other.

The ratio is a way of comparing two quantities of the same kind by using division. The ratio formula for two numbers a and b is given by a: b or a/b

Given:

For every 11 crickets Greta feeds Draco, she always feeds Lizzy 8 crickets.

Let solve it with an equality

11/8 = 77/x

We want to solve for x.

We can do so by finding how much larger the second fraction is than the first.

In this case, 77 is 7 times larger than 11.(77/11 = 7)

So, we know that x must be 7 times larger than 8( because the fractions are proportional)

Hence, x is 7 times larger than 8, we can use 7 times 8 to find the value.

7 times 8 is 56.

56 crickets for Lizzy.

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Answer:

$1350.68 to nearest cent.

Step-by-step explanation:

At the beginning $500 is deposited and this accumulates interest for 3 years At the end of first year it increases to 500( 1 + r) dollars

Then at the end of the 2 years its value is

500(1+ r)(1 + r)(

and at the end of 3 years value =

500(1 + r)(1 + r)(1 + r)

= 500(1 + r)^3 dollars

and as 1 + r = x we have:

500x^3 dollars

In the same way 200 for 2 years = 200x^2

and 600 for 1 year = 600x dollars.

Total = 500x^3 + 200x^2 + 600x.

b.

So, if the interest r = 2 % (= 0.02)

and x = 1.02

Total value after 3 years

= 500(1.02)^3 + 200(1.02)^2 + 600(1.02)

= 530.604 + 208.08 + 612

= $1350.684

The slope on the line containing the points (14,-42) is 1.06, as stated in the preceding sentence (-48,24).

The % slope is calculated by multiplying the distance between two locations by the differences in elevation above them. The difference in height between two places is referred to as "rise." The distance between it sites is known as the run. Therefore, the formula for percent slope is (rise / run) x 100.

The slope's formula is as follows:

m = (y₂-y₁)/x₂-x₁)

In the formula, replace the point values as follows:

m = (24-(-42))/(-48-14)

Make the fraction simpler:

m = (24-(-42))/(-48-14)

m = 66/-62

m = 1.06

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Based on the information, it can be inferred that Mr. Incredible did more work than Dash moving the train car.

To calculate the work that Mr. Incredible and Dash did moving the train car, we must apply the following mathematical formula:

According to the above, we only have to replace the values according to each case.

According to the above, it can be inferred that Mr. Incredible made more effort than Dash because they did 500,000 J and 500 J of work respectively.

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Answer: 1067/10000 is a fraction in simplest form. where, 0.1067 is a decimal, 10.67% is a percentage.

Step-by-step explanation:

Answer:

Step-by-step explanation:

To determine how long it will take for Louise to reach her goal of $30,000, we can use the formula for compound interest:

A = P * (1 + r/n)^(nt)

where:

A is the amount of money Louise will have after "t" years,

P is the initial investment of $20,000,

r is the annual interest rate of 4.28%,

n is the number of times the interest is compounded per year (12 times per year), and

t is the number of years.

We can rearrange this formula to solve for t:

t = (log(A/P)) / (log(1 + r/n))

Plugging in the values:

t = (log(30000/20000)) / (log(1 + (0.0428/12)))

t = 5.97 years

Rounding to the nearest tenth of a year, Louise will need to wait 6.0 years in order to reach her goal of $30,000.

Answer:

25 minutes

Step-by-step explanation:

The time difference between 1:25 and 1:50 is 25 min

We can fit 33 books on a 42-inch shelf if each book is 1 1/4 inches wide.

Using a unitary method, we can easily solve problems that involve proportional relationships between different units. In this problem, we used the unitary method to determine how many books can fit on a shelf based on its length and the width of one book.

To find out how many books can fit on a 42-inch shelf, we need to divide the length of the shelf by the width of one book. In this case, each book is 1 1/4 inches wide. However, it's important to convert this fraction to a decimal so we can do the math more easily. To do this, we can divide 1 by 4 and add it to 1 1/4:

1/4 = 0.25

1 1/4 = 1 + 0.25 = 1.25

Now that we know each book is 1.25 inches wide, we can use the unitary method to find how many books can fit on the shelf:

1 book = 1.25 inches

x books = 42 inches

To solve for x, we can cross-multiply:

1 book * 42 inches = 1.25 inches * x books

42 = 1.25x

Finally, we can divide both sides by 1.25 to isolate x:

42 / 1.25 = x

33.6 = x

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a) "What is your age?" is a quantitative data.

b) "Are you male or female?" is a categorical data.

c) "When did you first start reading the wsj?" is a categorical data.

d) "How long have you been in your present job or position?" is a quantitative data.

e) "What type of vehicle are you considering for your next purchase?" is a categorical data.

(a) "What is your age?" - This question provides quantitative data because age is a numerical value that can be measured and ordered in a meaningful way. Respondents could give an answer such as "25", "45", or "70", for example, which can be used to calculate statistics such as the mean or median age of the survey population.

(b) "Are you male or female?" - This question provides categorical data because the responses fall into discrete, non-numeric categories (in this case, "male" or "female"). It's not possible to order the responses in a meaningful way, since there is no inherent numerical value associated with being male or female.

(c) "When did you first start reading the WSJ?" - This question provides categorical data because the possible responses fall into discrete, non-numeric categories (high school, college, early career, mid career, late career, or retirement). While it's possible to order the categories in a logical sequence, they don't represent numerical values.

(d) "How long have you been in your present job or position?" - This question provides quantitative data because the responses can be measured as numerical values (for example, "3 years", "10 years", or "25 years"). The data can be used to calculate statistics such as the average length of time that respondents have been in their current position.

(e) "What type of vehicle are you considering for your next purchase?" - This question provides categorical data because the possible responses fall into discrete, non-numeric categories (sedan, sports car, SUV, minivan, etc.). While it's possible to order the categories in a logical sequence based on size, price, or other factors.

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According to the model, around 521 people will be infected in three days.

A unitary method is a mathematical technique where we use ratios and proportions to find the value of an unknown quantity.

Let's start by breaking down the problem. We know that there are currently 392 people infected and the virus is spreading at a rate of 11% each day. This means that for every 100 people, 11 people are getting infected. To calculate how many people will be infected in three days, we need to use a unitary method.

To do this, we need to calculate the total increase in the number of infected people over three days. Since the virus is spreading at a rate of 11% each day, the total increase over three days will be 33% (11% x 3). We can then use this percentage increase to calculate the total number of people infected in three days.

To find the total number of people infected in three days, we can use the following formula:

Total infected = current infected + (current infected x percentage increase)

Plugging in the values from the problem, we get:

Total infected = 392 + (392 x 0.33)

Total infected = 392 + 129.36

Total infected ≈ 521

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Hi there, here's your answer:

Given, a basketball team averaged 68 points per game in the last season and averaged 77 points per game in the present season.

To find:

The approximate percentage of increase.
Solution:

If 68 points was the average last season, and 77 points was the increase this season, then the number of increase in points is 9.

Also we have that % increase = [tex]\frac{Difference}{Original}[/tex] × 100

Which is [tex]\frac{9}{68}[/tex] × 100 = 0.1323 × 100 = 13.23%

Therefore, the approximate percent increase is 13%.

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(a) The angle measurement of first unknown angle is c = 80 degrees

(b) The angle measurement of second unknown angle is y = 110 degrees

Trigonometry is a branch of mathematics dealing with the relationship between the ratios of the sides of a right-angled triangle with its angles.

(a) You can pick pair of starting angles a = 30 degrees and b = 70 degrees

The angle measurement of first unknown angle will be:

a + b + c = 180  (sum of angles in a triangle is 180 degrees)

c = 180 - a - b

c = 180 - 30 - 70

c = 80 degrees

(b) The angle measurement of second unknown angle will be:

y = 180 - b  (sum of angles on a straight line is 180 degrees)

y = 180 - 70

y = 110 degrees

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Answer:

C. 77.3% decrease

Step-by-step explanation:

To calculate the percent change, we can use the formula:

percent change = (new value - old value) / old value * 100

Plugging in the values, we get:

percent change = (20 - 88) / 88 * 100 = -68 / 88 * 100 = -0.772727 * 100 = -77.3

Since the new value is lower than the old value, this is a decrease, and the answer is -77.3, or 77.3% decrease.

Using petid as a primary key in the pet relation is generally a good way to uniquely identify each data record in the relation. However, in some cases, it may be necessary to include personid as part of the primary key of the pet relation.

This is because each pet should have a unique identifier, and petid is specifically designed to serve this purpose. This would be the case if a person can have more than one pet in the database, and if the same petid value is used for more than one pet (which would violate the uniqueness requirement of a primary key).

By including personid as part of the primary key of the pet relation, we ensure that each pet in the database has a unique identifier (i.e., a unique combination of petid and personid). This allows us to avoid any confusion that might arise if two or more pets in the database had the same petid value. It also allows us to link each pet to its owner via the personid attribute, which can be useful for querying and reporting on the data.

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Answer:

$3.35

Step-by-step explanation:

$50.25 ÷ 15 gallons = $3.35 a gallon

The graph of the function f(x) = x(x + 5)(x - 2) have x intercepts at x = 0, -5 and 2

Graph is a mathematical representation of a network and it describes the relationship between lines and points.

An equation is an expression that shows the relationship between two or more numbers and variables.

Given the equation:

f(x) = x(x + 5)(x - 2)

x(x + 5)(x - 2) = 0

x = 0, x + 5 = 0, x - 2 = 0

x = 0, -5 and 2

The graph of the function f(x) = x(x + 5)(x - 2) have x intercepts at x = 0, -5 and 2

Hence, the graph of the function f(x) = x(x + 5)(x - 2) have x intercepts at x = 0, -5 and 2

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Answer:

Step-by-step explanation:

2, there are 4, making it the most.

For the given system of equations, the answers are of the given choices (A), (B) and (D).

A group of two or more equations with shared variables is referred to as a system of linear equations. Finding the value of the unknown variables employed in the equations that must satisfy both equations is necessary to solve a system of equations.

Given equations are -

y - 10 = 2x ⇒ y = 2x + 10

1/2y = x + 5 ⇒ y = 2x + 10

We can observe from the equation, that both the lines are same,

So any pair of values (x, y) that satisfy the equation y = 2x + 10 is a solution to the system. For example:

(0, 10) is a solution, since y = 2(0) + 10 = 10 and (1/2).10 = 0 + 5 =

(1, 12) is a solution, since y = 2(1) + 10 = 12 and (1/2).12 = 6 = 1 + 5

(2, -6) is a not solution, since y = 2(2) + 10 = 14 and (1/2)(-6) = 7 = 2 + 5

(-5, 0) is a solution, since y = 2(-5) + 10 = 0 and (1/2)(0) = 0

Therefore, the answer is of the given choices are (A), (B), (D).

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a) The Equation is  7.65x + 50 = 149.45.

b) The customer used the car for 13 hours.

c)  If the car used for 2 days i.e., 48 hours then the amount will be $471.12

Equations are mathematical statements with two algebraic expressions flanking the equals (=) sign on either side.

Coefficients, variables, operators, constants, terms, expressions, and the equal to sign are some of the components of an equation. The "=" sign and terms on both sides must always be present when writing an equation.

Given that;

Members of a car sharing program pay a fee of $50 per month plus $7.65 for every hour they use a car.

And, a members bill was $149.45 last month.

a) Let number of hours for the customer use a car last month = x

So, 7.65x + 50 = 149.45

7.65x = 149.45 - 50

7.65x = 99.45

x = 13

b) The customer used the car for 13 hours.

c) If the car used for 2 days i.e., 48 hours

= 7.65x + 50

= 7.65(48)+ 50

= 471.2

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Answer: 22

Step-by-step explanation:

f(x) is basically the y of the function and we sent x=3. go back to the function and plug in 3 in the x. then solve 3^2=9  2x9=18 18+4=22 BOOOM  MATHH

The required, there is no highest common factor between 4454 and 121j²k. None of the options are correct.

The highest common factor (HCF) of two or more numbers is the largest number that divides all of the numbers exactly.

Here,
To find the greatest common factor (GCF) of 4454 and 121j²k, we need to factor both numbers into their prime factors and then identify the common factors.

Since 4454 is an even number and 121 is an odd number so there is no prime highest common factor between the given number.

Thus, none of the options are correct.

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The Selling price of a book with a retail of R 100 and R 88 will be 99.625 and 87.625 respectively.

The selling price of a good or service is the final cost to the seller, or what the buyer actually pays. A commodity or service in a specific amount, weight, or measurement can be exchanged.

It is one of the most crucial things for a business to decide. It is significant since it determines whether or not it will survive. Sales of a product are directly impacted by its price.

According to the question,

Discount = 3/8 of the retail price.

Now,

When retail price is 100,

Selling price [tex]= 100-3/8[/tex]

[tex]=99.625[/tex]

When retail price is 88.

Selling price [tex]= 88-3/8[/tex]

[tex]=87.625[/tex]

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An equation of the line of best fit for the data is y = -0.9x + 13.6.

The correlation coefficient (r) for the data to the nearest thousandth is -0.964.

In order to determine a linear equation in slope-intercept form for the line of best fit that models the data points described above, we would use a scatter plot (graphing calculator).

On the Excel worksheet, you should right click on any data point on the scatter plot, select format trend line, and then tick the box to display a linear equation for the line of best fit (trend line) on the scatter plot.

From the scatter plot (see attachment) which models the relationship between the data set, a linear equation for the line of best fit is given by:

y = -0.895x + 13.600.

Rounding up as required, we have:

y = -0.9x + 13.6.

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Complete Question:

Use a graphing calculator to find an equation of the line of best fit for the data in the table. Round the slope and y-intercept to the nearest tenth. Then Identify and interpret the correlation coefficient.

X- 10.1 9.8 9.7 9.4 8.9 8.7 8.4 8.1

Y- 4.3 4.8 5.3 5.2 5.6 5.8 6.1 6.3

The equation of the line of best fit is y=

To the nearest thousandth, the correlation coefficient is r=

Answer:

Step-by-step explanation:

To build a sequence, you have to create a rule. For example, if the rule is +2, then you add 2 to 10 to get 12, and then you add 2 to 12 to get 14, and so on. Your sequence would then be 10, 12, 14, 16, 18.

Answer:

hundredths

Step-by-step explanation: