The sales tax rate for a local county is 8.4%. If an item costs $391 (before tax), how much sales tax will be due?

Final answer:

There can be a total of 11,175 two-person conversations at the party.

Explanation:

In a party with 150 people, the number of two-person conversations that can occur can be calculated using the formula for combinations. Since each conversation involves two people, we need to choose 2 people from the total of 150. The formula for combinations is:

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

Where n is the total number of people and r is the number of people we need to choose. Plugging in the values, we have:

C(150, 2) = 150! / (2!(150-2)!)

C(150, 2) = (150 ×149) / (2 ×1)

C(150, 2) = 11175

Therefore, there can be a total of 11,175 two-person conversations at the party.

Final answer:

At a party with 150 people, there can be 11175 unique two-person conversations, calculated using the combination formula 150C2.

Explanation:

The question is asking how many two-person conversations can occur at a party with 150 people. This is a classic combination problem where we need to calculate the number of unique pairs that can be made from 150 people. Since the order in which the pair is chosen does not matter, we use the combination formula nCr = n! / (r!(n-r)!), where 'n' is the total number of people and 'r' is the group size (in this case, 2 for a two-person conversation).

For 150 people, the calculation is:

150C2 = 150! / (2!(150-2)!) = 150! / (2! x 148!) = (150 x 149) / (2 x 1) = 11175.

Therefore, there can be 11175 unique two-person conversations at a party with 150 people.

The equation of the parabola that models the movement of the football is y = -2x² + 5x + 12. The time at which the ball hits the ground is x = 4 seconds.

The quadratic equation is defined as a function containing the highest power of a variable is two.

a. We know that the general form of the quadratic equation is y = ax² + bx + c, where a, b, and c are constants.

We are given three points that the football passes through: (1, 15), (2, 14), and (3, 9).

We can substitute these points into the quadratic equation and solve for a, b, and c.

For the first point, we have: 15 = a(1)² + b(1) + c

For the second point, we have: 14 = a(2)² + b(2) + c

For the third point, we have: 9 = a(3)² + b(3) + c

Solving this system of equations using elimination gives us:

a = -2

b = 5

c = 12

Therefore, the equation of the parabola that models the movement of the football is y = -2x² + 5x + 12.

b. To find the time at which the ball hits the ground, we can set the value of y equal to 0 and solve for x.

y = -2x² + 5x + 12

0 = -2x² + 5x + 12

-12 = -2x² + 5x

-2x² + 5x - 12 = 0

We can use the quadratic formula to solve for x:

x = (-5 +/- √(5² - 4(-2)(-12)))/(2(-2))

x = (-5 +/- √(25 + 96))/(-4)

x = (-5 +/- √(121))/(-4)

x = (-5 +/- 11)/(-4)

Therefore, x = 4 or x = -3/2.

The time at which the ball hits the ground is x = 4 seconds.

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To find the inverse of f(x) = x² + 7, replace f(x) with y and solve for x, resulting in the inverse function f–1(x) = √(x - 7), considering the domain x ≥ 7.

To find the inverse function of f(x) = x² + 7, we must first replace f(x) with y, giving us y = x² + 7. To find the inverse, we solve for x. We start by subtracting 7 from both sides to get y - 7 = x². Taking the square root of both sides, we get x = ±√(y - 7).

Since the square root has two values (positive and negative), we choose the one that matches the domain and range of the original function. If f(x) is defined for all nonnegative values of x, the inverse would be f–1(x) = √(x - 7). If f(x) includes negative values of x, then we would consider both, resulting in two different functions.

However, because we're dealing with f(x) that implies only one output for each input without restrictions, we consider the principal square root. Thus, the equation for the inverse function is f–1(x) = √(x - 7), considering the domain where x is greater than or equal to 7.

Final answer:

The average speed of the car is 86.67 km/h.

Explanation:

The average speed of a car can be calculated by dividing the total distance traveled by the total time taken. In this case, the car traveled 85 km from town A to town B and then 45 km from town B to town C, for a total distance of 85 km + 45 km = 130 km. The total trip took 1.5 hours. To find the average speed, divide the total distance by the total time: 130 km / 1.5 h = 86.67 km/h.

Answer:

its c

Step-by-step explanation:

Answer:

The solution to the given inequality is (-∞,5].

Step-by-step explanation:

An inequality is a relation which makes a non-equal comparison between two numbers.

Given : 7-3(x+5)+8x≤17

=7-3(x+5)+8x ≤ 17

= 7- 3x - 15 + 8x ≤ 17

= -8 + 5x ≤ 17

Adding 8 on both sides:

= -8 +8+ 5x ≤ 17+8

= 5x ≤ 25

x ≤ 5

The solution to the inequality : (-∞,5].

Distance between the points A (-4, 2) and B (15, 6) is 19.41.

Here,

The points are A (-4, 2) and B (15, 6).

We have to find the distance between the points A (-4, 2) and B (15, 6).

What is Distance between two points?

Distance between two points A (x₁, y₁) and B (x₂, y₂) is given by:

[tex]D_{AB} = \sqrt{(x_{2}-x_{1} )^2+(y_{2} -y_{1} )^2}[/tex]

Now,

Distance between the points A (-4, 2) and B (15, 6) is;

[tex]D_{AB} = \sqrt{(15-(-4))^2+(6-2)^2}[/tex]

       [tex]= \sqrt{19^2+4^2}[/tex]

       [tex]= \sqrt{361+16}[/tex]

       [tex]= \sqrt{377}[/tex]

       [tex]= 19.41[/tex]

Hence, Distance between the points A (-4, 2) and B (15, 6) is 19.41.

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The equation for the function f would be; f(x) = -1.75x + 18.75.

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

Function is a type of relation, or rule, that maps one input to specific output.

Given that f is a linear function such that f(5) = 10 and f(9) = 3, then

Consider that the function of x would be;

f(x) = -1.75x + 18.75

Now plug x = 5 in the given function, if it satisfy the function

f(5) = -1.75(5) + 18.75

f (5) =10

Again plug x = 9 in the given function, if it satisfy the function

f(9) = -1.75(9) + 18.75

f(9) =3

Therefore, the equation for the function f would be; f(x) = -1.75x + 18.75.

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The truck's displacements in the North-South and East-West directions are calculated separately. The final displacement is 5 blocks South and 12 blocks East.

To solve this problem, we need to consider the truck's displacement in the North-South direction and the East-West direction separately.

Starting with the North-South direction, the truck moves 21 blocks North and then 26 blocks South. Thus, its total displacement in the North-South direction is 21 - 26 = -5 blocks. The negative sign indicates that the truck is 5 blocks South from its starting point.

Considering the East-West direction, the truck moves 12 blocks East. Therefore, its total displacement in the East-West direction is +12 blocks.

Overall, the displacement of the truck from the origin is 5 blocks South and 12 blocks East.

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Answer:

[tex]m=\frac{s-c}{c}[/tex]

Step-by-step explanation:

The given expression is

[tex]s=c+mc[/tex]

Now, to find the expression for [tex]m[/tex], we just have to isolate it. First, we have to move the term [tex]c[/tex] to the other side of the equation, and then to move the coefficient [tex]c[/tex], which is gonna pass to the other side dividing.

[tex]s=c+mc\\s-c=mc\\\frac{s-c}{c}=m\\m=\frac{s-c}{c}[/tex]

Therefore, the percent markup is defined as the difference between the selling price and cost, divided by that cost.

The equation that models the data in the table is:

                        [tex]c=22d[/tex]

The table that represent the days and cost is given by:

       Days Cost

           2          44

           3          66

           5           110

           6          132

We see that the cost is a constant multiple of  the number of days.

i.e. the equation is given by:

             c=22d

i.e. the relationship is linear.

( Since, when d=2

we have: c=22×2=44

when d=3 we have:

c=22×3=66

and so on )

The correct answer is option 3. The equation for the line of reflection that maps the trapezoid onto itself is y = 3.

To determine the line of reflection for a trapezoid that maps onto itself, we need to identify the axis of symmetry.

We can analyze each one:

1. x = 0 represents a vertical line of reflection. If the trapezoid were reflected over this line, the left and right sides would be swapped. This would not map the trapezoid onto itself unless the trapezoid is symmetric about the y-axis, which is not specified.

2. x = 3 also represents a vertical line of reflection. This would reflect the trapezoid over a vertical line three units to the right of the y-axis. Again, this would not map the trapezoid onto itself unless the trapezoid is symmetric about the line x = 3, which is not specified.

3. y = 3 represents a horizontal line of reflection three units above the x-axis. If the trapezoid has its bases parallel to the x-axis and the midline of the trapezoid is at y = 3, then reflecting over this line would indeed map the trapezoid onto itself. This is because the top half of the trapezoid would be a mirror image of the bottom half across the line y = 3.

4. y = 0 represents a horizontal line of reflection along the x-axis. Reflecting the trapezoid over the x-axis would flip it upside down, which would not map the trapezoid onto itself unless the trapezoid is symmetric about the x-axis, which is not typical for a trapezoid.

The complete question is:

What is the equation for the line of reflection that maps the trapezoid onto itself?

1. x = 0

2. x = 3

3. y = 3

4. y = 0

The missing part of the unit rate in the given situation is 8 students per group. This is obtained from dividing the total number of students (40) by the total number of groups (5).

To find the missing part of the unit rate, we'll need to divide the total number of students (40) by the total number of groups (5). This is because a unit rate describes how many units of the first type of quantity corresponds to one unit of the second type of quantity.

So in this case, the unit rate would be 40 ÷ 5 = 8. Therefore, the missing part of the unit rate is 8 students per group.

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The Panthers are expected to win approximately 73 games out of 110 based on their current win rate.

To find out how many games the Panthers will win in a normal 110-game season based on their current winning rate from the beginning of the season, we use a simple proportion. Initially, they won 40 games out of 60, which gives us a winning ratio.

The ratio can be written as:

40 wins / 60 games = number of wins / 110 games

To find the number of wins, we cross-multiply and solve for the unknown:

(40 wins / 60 games) * 110 games = number of wins

After the calculation:

40 * 110 / 60 ≈ 73.33

As we need to round to the nearest game, it gives us approximately 73 games out of 110.

The maximum age of a fossil that could be dated using 40K is approximately 5.36 billion years.

Potassium-40 (40K) has a half-life of 1.25 billion years.

The minimum detectable amount for dating using 40K is 0.1%. If a dinosaur is dated using 40K to be 67 million years old, we can calculate the maximum age of a fossil that could be dated using 40K.

To find the maximum age, we can set up a proportion using the half-life of 40K:

(67 million years) / (1.25 billion years) = (x years) / (100%)

Solving for x, we get:

x = (67 million years) * (100%) / (1.25 billion years)

Calculating this, we find that the maximum age of a fossil that could be dated using 40K is approximately 5.36 billion years.