The table below shows the average annual cost of health insurance for a single individual, from 1999 to 2019, according to the Kaiser Family Foundation.YearCost1999$2,1962000$2,4712001$2,6892002$3,0832003$3,3832004$3,6952005$4,0242006$4,2422007$4,4792008$4,7042009$4,8242010$5,0492011 $5,4292012$5,6152013$5,8842014$6,0252015$6,2512016$6,1962017$6,4352017$6,8962019$7,186(a) Using only the data from the first and last years, build a linear model to describe the cost of individual health insurance from 1999 onward. Use t to represent years after 1999 (treating 1999 as year 0).Pt = (b) Using this linear model, predict the cost of insurance in 2030.$ (c) = According to this model, when do you expect the cost of individual insurance to reach $12,000? Give your answer as a calendar year (ex: 2020)..
Answers
The given data plot will look thus:
a) Building a model using just the 1999 and 2019 years:
[tex]\begin{gathered} 1999\rightarrow0\rightarrow2196 \\ 2019\rightarrow20\rightarrow7186 \\ \text{Havng} \\ x_1=0,y_1=2196 \\ x_2=20,y_2=7186 \\ \frac{y-y_1}{x-x_1}=\frac{y_2-y_1}{x_2-x_1}_{} \\ \text{The model will be:} \\ P_t=249.5t+2196 \end{gathered}[/tex]b) The cost of insurance in 2030
[tex]\begin{gathered} P_t=249.5t+2196 \\ t=2030-1999=31 \\ \text{The cost of insurance in 2030 therefore will be:} \\ =249.5(31)+2196 \\ =7734.5+2196 \\ =\text{ \$9930.5} \end{gathered}[/tex]c) When do we expect the cost to reach $12,000
[tex]\begin{gathered} P_t=249.5t+2196 \\ 12,000=249.5t+2196 \\ 12000-2196=249.5t \\ 9804=249.5t \\ \frac{9804}{249.5}=\frac{249.5t}{249.5} \\ 39.2946=t \\ Since\text{ t = year -1999} \\ 39.2946+1999=\text{year} \\ 2038.2946=\text{year} \\ Since\text{ we are to give our answer as an exact year} \\ \text{The year will be }2039. \end{gathered}[/tex]
Related Questions
Write the following numbers in decreasing order: −4; 1 2/3 ; 0.5; −1 3/4 ; 0.03; −1; 1; 0; -103; 54
Answers
Decreasing order means from largest to smallest
The ordered list is:
54, 1 2/3, 1, 0.5, 0.03, 0, -1, -1 3/4, -4, -103
Question 16
Given AEFHAGFH below, what is the measure of GFH?
F
21.6°
E<
(6x - 12)° H
G
1 pts
Answers
The most appropriate choice for congruency of triangles will be given by-
[tex]\angle GFH =68.4^{\circ}\\[/tex]
What is congruency of triangles?
Two triangles are said to be congruent if all the corrosponding sides and the corrosponding angles of the triangle are equal.
There are five axioms of congruency. They are -
SSS axioms, SAS axioms, ASA axiom, AAS axiom, RHS axiom.
Here,
[tex]\Delta EFH \cong \Delta GFH[/tex] [Given]
[tex]\angle E = \angle G = 21.6^{\circ}[/tex] [Corrosponding parts of congruent triangles are congruent]
[tex]\angle GFH[/tex] = 180 - (90 + 21.6) [Sum of the three angles of a triangle is 180°]
[tex]\angle GFH = 180 - 111.6\\\angle GFH =68.4^{\circ}\\[/tex]
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slope= 2; point on the line (-2,1) in slope intercept form I know y=m*x+b but all I know is 2 would be m
Answers
y=2x+5
1) Since we were told the slope is m=2, one point on the line (-2,1), and the slope-intercept form is:
[tex]y=mx+b[/tex]2) The next step is to find the value of "b", the y-intercept. So, let's pick that point, the slope, and plug them into the Slope-Intercept form:
[tex]\begin{gathered} y=mx+b,m=2,(-2,1) \\ 1=2(-2)+b \\ 1=-4+b \\ 1+4=b \\ b=5 \end{gathered}[/tex]3) Now that we know the y-intercept (b), we can write the function's rule as
[tex]y=2x+5[/tex]if a ray QT bisects
Answers
EXPLANATION
If a ray QT bisects
(3x - 5) + (x+1) = 180 [By the Linear Pair Theorem]
Removing the parentheses:
3x - 5 + x + 1 = 180
Grouping like terms:
3x + x + 1 - 5 = 180
Adding like terms:
4x -4 = 180
Adding +4 to both sides:
4x = 180 + 4
Adding numbers:
4x = 184
Dividing both sides by 4:
x = 184/4
Simplifying:
x=46
Now, we need to compute the resulting angles:
m m
As QT bisects
47/2 = 23.5 degrees
The answer is 23.5°
its composition of fractions in pre-calculus.I know how to do these types of questions, im just not sure how u would set it up if there are 2 x's in one of the equations.
Answers
Answer:
(f o g)(x) = x
Explanation:
Given f(x) and g(x) defined below:
[tex]\begin{gathered} f(x)=\frac{1-x}{x} \\ g(x)=\frac{1}{1+x} \end{gathered}[/tex]The composition (f o g)(x) is obtained below:
[tex]\begin{gathered} (f\circ g)(x)=f\lbrack g(x)\rbrack \\ f(x)=\frac{1-x}{x}\implies f\lbrack g(x)\rbrack=\frac{1-g(x)}{g(x)} \end{gathered}[/tex]Substitute g(x) into the expression and simplify:
[tex]\begin{gathered} f\lbrack g(x)\rbrack=\frac{1-g(x)}{g(x)}=\lbrack1-g(x)\rbrack\div g(x) \\ =(1-\frac{1}{1+x})\div(\frac{1}{1+x}) \\ \text{ Take the LCM in the first bracket} \\ =\frac{1(1+x)-1}{1+x}\div\frac{1}{1+x}\text{ } \\ \text{Open the bracket} \\ =\frac{1+x-1}{1+x}\div\frac{1}{1+x}\text{ } \\ =\frac{x}{1+x}\times\frac{1+x}{1}\text{ } \\ =x \end{gathered}[/tex]Therefore, the composition (f o g)(x) is x.
Determine if the side lengths could form a triangle. Use an inequality to prove the answer. Inequality must be used.
Answers
The side lengths given form a triangle
Explanation:Let the lengths of the sides of the triangle be "a", "b" and "c"
For the length to form sides of a triangle, the sum of any two sides of the triangle must be greater than the third as shown:
[tex]\begin{gathered} a+b>c \\ a+c>b \\ b+c>a \end{gathered}[/tex]Given the sides of the triangle as 34km, 27km, and 58km
Let a = 34km, b = 27km and c = 58km
Substituting these values in the expression above to check if it is true:
[tex]\begin{gathered} 34+27=61>58 \\ 34+58=92>27 \\ 27+58=85>34 \end{gathered}[/tex]Since the inequality expression supports the theorem above, hence the side lengths given form a triangle
f(x)=3x-4g(x)=-x^2+2x-5h(x)2x)^2+1j(x)=6x^2-8xk(x)=-x+7calculate (g+j)(x)
Answers
To calculate (g+j)(x) we need the function:
[tex]\begin{gathered} g(x)=-x^2+2x-5 \\ j(x)=6x^2-8x \end{gathered}[/tex]and we can made the addition so:
[tex]\begin{gathered} (g+j)(x)=g(x)+j(x) \\ (g+j)(x)=-x^2+2x-5+6x^2-8x \end{gathered}[/tex]and we can simplify
[tex](g+j)(x)=5x^2-6x-5[/tex]Find x when the f(x) = 350 - 125x ; when f(x) = 0.
Answers
ANSWER
x = 2.8
EXPLANATION
The function given is:
f(x) = 350 - 125x
We want to find the value of x when f(x) = 0.
This means that:
[tex]\begin{gathered} f(x)\text{ = 350 - 125x} \\ \Rightarrow\text{ 0 = 350 - 125x} \\ \Rightarrow\text{ 125x = 350} \\ \frac{125x}{125}\text{ = }\frac{350}{125} \\ x\text{ = 2.8} \end{gathered}[/tex]That is the value of x
For what values of a are the following expressions true?/a+5/=-5-a
Answers
Explanation:
The expression is given below as
[tex]|a+5|=-5-a[/tex]Concept:
We will apply the bsolute rule below
[tex]\begin{gathered} if|u|=a,a>0 \\ then,u=a,u=-a \end{gathered}[/tex]By applying the concept, we will have
[tex]\begin{gathered} \lvert a+5\rvert=-5-a \\ a+5=-5-a,a+5=5+a \\ a+a=-5-5,a-a=5-5 \\ 2a=-10,0=0 \\ \frac{2a}{2}=\frac{-10}{2},0=0 \\ a=-5,0=0 \end{gathered}[/tex]Hence,
The final answer is
[tex]a\leq-5[/tex]RecoverySolve for x usingcross multiplication.2x + 132x11 -=x + 22x = [?]Enter
Answers
Answer:
x = 4
Step-by-step explanation:
Cross-multiplying means multiplying the numerator of one side by the denominator of the other side.
So, let's multiply the sides:
[tex]\begin{gathered} \frac{2x+1}{3}=\frac{x+2}{2} \\ 2\cdot(2x+1)=3\cdot(x+2) \end{gathered}[/tex]Now, we can solve each side:
[tex]\begin{gathered} 4x+2=3x+6 \\ 4x-3x=6-2 \\ 1x=4 \\ x=4 \end{gathered}[/tex]So, x = 4.
How does g(t) = 4t change over the interval t = 3 to t = 4?
Answers
Over the interval t = 3 to t = 4, g(t) increases.
The increasing factor (f) is computed as follows:
[tex]f=\frac{g(4)}{g(3)}[/tex]where g(4) is g(x) at t = 4, and g(3) is g(x) at t = 3. Substituting with the formula of g(t) and evaluating each expression, we get:
[tex]\begin{gathered} f=\frac{4^4}{4^3} \\ f=\frac{4\cdot4^3}{4^3} \\ f=4 \end{gathered}[/tex]Then, g(t) increases by a factor of 4
what is the value of the q that makes the equation true? 3(q+4)-10q=2q+3
Answers
Distribute:
3q + 12 - 10q = 2q + 3
Combine like terms:
-7q + 12 = 2q + 3
Inverse operation (subtract 3 on both sides):
-7q + 9 = 2q
Inverse operation; Add -7q on both sides:
9 = 9q
Solve: Divide 9 on both sides to single out the variable
[ q=1 ]
Solve each system of equations algebraically.[tex]y = {x}^{2} + 4 \\ y = 2x + 7[/tex]
Answers
From the problem, we two equations :
[tex]\begin{gathered} y=x^2+4 \\ y=2x+7 \end{gathered}[/tex]Since both equation are defined as y in terms of x, we can equate both equations.
[tex]\begin{gathered} y=y \\ x^2+4=2x+7^{} \end{gathered}[/tex]Simplify and solve for x :
[tex]\begin{gathered} x^2+4=2x+7 \\ x^2-2x+4-7=0 \\ x^2-2x-3=0 \end{gathered}[/tex]Factor completely :
[tex]\begin{gathered} x^2-2x-3=0 \\ (x-3)(x+1)=0 \end{gathered}[/tex]Equate both factors to 0 then solve for x :
x - 3 = 0
x = 3
x + 1 = 0
x = -1
We have two values of x, x = 3 and -1
Substitute x = 3 and -1 to any of the equation, let's say equation 2 :
For x = 3
y = 2x + 7
y = 2(3) + 7
y = 6 + 7
y = 13
One solution is (3, 13)
For x = -1
y = 2x + 7
y = 2(-1) + 7
y = -2 + 7
y = 5
The other solution is (-1, 5)
The answers are (3, 13) and (-1, 5)
The marching band director is standing on a platformoverlooking the band practice. The pit section is located 8feet from the base of the platform. If the angle ofdepression from the band director to the pit section is 67°find the height of the platform.
Answers
Through trigonometry, we calculated that the height of the platform is 18.8 feet.
The director of the marching band is observing the band practice from a platform. 8 feet separate the base of the platform from the pit area. If the pit section's angle of depression is 67 degrees from the band director,
The angle formed by the horizontal line and the item as seen from the horizontal line is known as the angle of depression. When the angles and the separation of an object from the ground are known, it is mostly used to calculate the distance between the two objects.
We have,
So, the Angle of Depression = [tex]\alpha[/tex] = 67
Let x be the height of the platform,
Tan [tex]\alpha = \frac{x}{8}[/tex]
[tex]Tan 67 = \frac{x}{8} \\\\2.35 =\frac{x}{8} \\x = 2.35 *8 = 18.8[/tex]
Hence, The height of the platform is 18.8 feet.
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help me solve the volume of the cylinder? 20 ft x 17 ft
Answers
Remember that the formula for the volume of a cylinder is:
[tex]V=\pi r^2h[/tex]Where:
• r, is the ,radius, of the base
,• h ,is the height of the cylinder
Notice that the base has a diameter of 20 ft. Therefore, the radius is 10 ft.
Using this data and the formula, we get that:
[tex]\begin{gathered} V=\pi(10^2)(17) \\ \rightarrow V=5340.71 \end{gathered}[/tex]The volume of the cylinder is:
[tex]2540.71ft^3[/tex]The volume of a square-based rectangular cardboard box needs to be at least 1000cm^3. Determine the dimensions that require the minimum amount of material to manufacture all six faces. Assume that there will be no waste material. The Machinery available cannot fabricate material smaller than 2 cm in length.
Answers
We have to find the dimensions of a box with a volume that is at least 1000 cm³.
We have to find the dimensions that require the minimum amount of material.
We can draw the box as:
The volume can be expressed as:
[tex]V=L\cdot W\cdot H\ge1000cm^3[/tex]The material will be the sum of the areas:
[tex]A=2LW+2LH+2WH[/tex]Since the box is square-based, the width and length are equal and we can write:
[tex]L=W[/tex]Then, we can re-write the area as:
[tex]\begin{gathered} A=2L^2+2LH+2LH \\ A=2L^2+4LH \end{gathered}[/tex]Now, we have the area expressed in function of L and H.
We can use the volume equation to express the height H in function of L:
[tex]\begin{gathered} V=1000 \\ L\cdot W\cdot H=1000 \\ L^2\cdot H=1000 \\ H=\frac{1000}{L^2} \end{gathered}[/tex]We replace H in the expression for the area:
[tex]\begin{gathered} A=2L^2+4LH \\ A=2L^2+4L\cdot\frac{1000}{L^2} \\ A=2L^2+\frac{4000}{L} \end{gathered}[/tex]We can now optimize the area by differentiating A and then equal the result to 0:
[tex]\begin{gathered} \frac{dA}{dL}=2\frac{d(L^2)}{dL}+4000\cdot\frac{d(L^{-1})}{dL} \\ \frac{dA}{dL}=4L+4000(-1)L^{-2} \\ \frac{dA}{dL}=4L-\frac{4000}{L^2} \end{gathered}[/tex][tex]\begin{gathered} \frac{dA}{dL}=0 \\ 4L-\frac{4000}{L^2}=0 \\ 4L=\frac{4000}{L^2} \\ L\cdot L^2=\frac{4000}{4} \\ L^3=1000 \\ L=\sqrt[3]{1000} \\ L=10 \end{gathered}[/tex]We now can calculate the other dimensions as:
[tex]W=L=10[/tex][tex]H=\frac{1000}{L^2}=\frac{1000}{10^2}=\frac{1000}{100}=10[/tex]Then, the dimensions that minimize the surface area for a fixed volume of 1000 cm³ is the length, width and height of 10 cm, which correspond to a cube (all 3 dimensions are the same).
Answer: the dimensions are length = 10 cm, width = 10 cm and height = 10 cm.
A tree casts you say shadow that is 9 feet long at the same time a person standing nearby casts a shadow that is 3 feet long if the person is five point feet tall how tall is the tree
Answers
we have that
Applying proportion
x/9=5.5/3
solve for x
x=9*(5.5/3)
x=16.5 ft
therefore
the answer is 16.5 ftI’m the relationship shown by the data linear, if so, model with an equation . A. The relationship is linear;
Answers
The relation is data if the difference between every 2 x is equal and the difference between every 2 y is equal
Since:
-5 - (-7) = -5 + 7 = 2
-3 - (-5) = -3 + 5 = 2
-1 - (-3) = -1 + 3 = 2
Since:
9 - 5 = 4
13 - 9 = 4
17 - 13 = 4
Then
The difference between every 2 x is constant and the difference between every 2 y constant
Then the relation is linear
Since the form of the linear equation is
[tex]y-y_1=m(x-x_{1)}[/tex]m is the rate of change of y with respect to x (the slope of the line)
(x1, y1) is a point on the line
Let us find m
[tex]\begin{gathered} m=\frac{\Delta y}{\Delta x} \\ \Delta y=4 \\ \Delta x=2 \\ m=\frac{4}{2} \\ m=2 \end{gathered}[/tex]Since x1 = -7 and y1 = 5, then
[tex]\begin{gathered} y-5=2(x--7) \\ y-5=2(x+7) \end{gathered}[/tex]What is the vertex of the graph of the function below?y = x^2 + 10x + 24O A. (-4,-1)O B. (-5, -1)O C. (-5,0)O D. (4,0)
Answers
For any given parabola in the form
[tex]f(x)=ax^2+bx+c[/tex]The vertex is the point:
[tex]V=(-\frac{b}{2a},f(-\frac{b}{2a}))[/tex]This way,
[tex]\begin{gathered} y=f(x)=x^2+10x+24 \\ \rightarrow a=1 \\ \rightarrow b=10 \\ \rightarrow c=24 \\ \\ \rightarrow-\frac{b}{2a}=-\frac{10}{2\cdot1}=-5 \\ \\ \rightarrow f(-5)=(-5)^2+10(-5)+24=-1 \end{gathered}[/tex]Therefore, the vertex is:
[tex]V(-5,-1)[/tex]Answer: Option B
Solve the following equations. (You may leave your answer in terms of logarithms or you can plug your answer into a calculator to get a decimal approximation.)
Answers
Given the equation:
[tex]200(1.06)^t=550[/tex]We divide each side by 200:
[tex]\begin{gathered} \frac{200}{200}(1.06)^t=\frac{550}{200} \\ 1.06^t=2.75 \end{gathered}[/tex]Now, we take the natural logarithm:
[tex]\begin{gathered} \ln (1.06^t)=\ln (2.75) \\ t\cdot\ln (1.06)=\ln (2.75) \\ \therefore t=\frac{\ln (2.75)}{\ln (1.06)} \end{gathered}[/tex]find the percent notation 7/10
Answers
A notation is a way of communicating through symbols or signs, or it might be a brief written message. A chemist notating AuBr for gold bromide is an illustration of a notation. A quick list of things to accomplish is an illustration of a notation.
Explain about the percent notation?Since one percent (symbolized as 1%) is equal to one hundredth of something, 100 percent stands for everything, and 200 percent refers to twice the amount specified.
A value or ratio that may be stated as a fraction of 100 is referred to as a percentage in mathematics. If we need to calculate a percentage of a number, we should divide it by its entirety and then multiply it by 100. The proportion therefore refers to a component per hundred. Per 100 is what the word percent means. The sign "%" is used to denote it.
When expressing a fraction as a percentage, we multiply the provided fraction by 100.7/10, which is 70%.
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Make a table for the graph labeled hours studies average grade
Answers
We can easily create a table with the first column labeled "hours studied" and second column labeled "average grade".
The hours studied are:
0, 1, 2, 3, and 4
The respective average grades are:
56, 75, 85, 90, 100
The table can look like this:
Answer:
To make the table, you must correlate the average test grade with the hours spent studying.
The graph shows the idea that the more we learn, the higher will be our test grades.
The table is attached.
0.0032% in fraction
Answers
Recall that the x% in fraction form is:
[tex]\frac{x}{100}\text{.}[/tex]Therefore 0.0032% as a fraction is:
[tex]\frac{0.0032}{100}=\frac{\frac{32}{10000}}{100}\text{.}[/tex]Simplifying the above result we get:
[tex]\frac{\frac{32}{10000}}{100}=\frac{32}{100\times10000}=\frac{1}{31250}\text{.}[/tex]Answer:
[tex]\frac{1}{31250}[/tex]Steve has been training for a 5-mile race. Before the race, he predicts he will finish in 42minutes. He actually finishes the race in 40 minutes. What is the percent error for hisprediction?
Answers
To find the percent error
percent error = | (actual - expected)/ actual| * 100 %
The actual is 40 and the expected is 42
percent error = | ( 40 - 42) / 40 | * 100 %
= | -2/40| * 100%
= .05 * 100 %
= 5%
Using pH=-log{H3O+}, what is pH for 3.4 X 10^-4 ?
Answers
The value of the pH for pH=-log{H3O+} is found as 3.47.
What is defined as the pH?The pH of aqueous or some other liquid solutions is a quantitative measure of their acidity or basicity. The concentration of hydrogen ion, which normally ranges between around 1 and 10∧14 gram-equivalents per litre, is converted into a number between 0 and 14. The concentration of hydrogen ion in pure water, which really is neutral (nor acidic and neither alkaline), is 10∧7 gram-equivalents per litre, corresponding to a pH of 7. A solution with such a pH less than 7 is classified as acidic, while one with pH greater than 7 is classified as basic, or alkaline.For the given equation,
pH = - log [H3O+]
and , H3O+ = 3.4 X 10^-4
The, the pH will be estimated as;
pH = - log [ H3O+]
pH = - log [ 3.4 x10 ^-4]
pH = - [log 3.4 + log 10^-4]
pH = - [0.53 + (-4)]
pH = -[-3.47]
pH = 3.47
Thus, the value of the pH is found as 3.47.
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Determine the vertex and the axis of symmetry based on the equation, y =-12 -8x - 36
Answers
Solution
Determine the vertex and the axis of symmetry based on the equation:
[tex]y=-x^2-8x-36[/tex]Therefore the correct answer is Option A
Sketch the vectors u and w with angle θ between them and sketch the resultant.|u|=45, |w|= 25, θ=30°
Answers
Step 1
Find the resultant of the vectors
[tex]undefined[/tex]The vertex of the parabola below is at the point
Answers
SOLUTION
The equation of a parabola in a vertex form is given
since the parabola is on the x-axis.
[tex]\begin{gathered} x=a(y-h)^2+k \\ \text{Where } \\ \text{Vertex}=(h,k) \end{gathered}[/tex]From the diagram given, we have
[tex]\text{vertex}=(-4,-2)[/tex]Substituting into the formula above, we have
[tex]\begin{gathered} x=a(y-h)^2+k \\ h=-4,k=-2 \end{gathered}[/tex]We have
[tex]\begin{gathered} x=(y-(-2)^2-4 \\ x=(y+2)^2-4 \end{gathered}[/tex]Since the parabola is a reflection from the parent function, then
[tex]a=-2[/tex]The equation of the parabola becomes
[tex]x=-2(y+2)^2-4[/tex]Answer; x = -2(y + 2)^2-4
HELP ME PLS!!!!!!!
Total consumption of fruit juice in a particular country in 2006 was about 2.15 billion gallons. The population of that country in 2006 was 400 million. What was the average number of gallons of fruit juice consumed per person in the country in 2006? using the per person amount from this problem, about how many gallons would your class consume?
Answers
Answer:
5.375 gallons/personStep-by-step explanation:
Total consumption of fruit juice in 2006:
2.15 billion gallonsThe population of the country:
400 million people.Average consumption of fruit juice per person in 2006 was:
2.15 billion / 400 million = 2.15 × 10⁹ / 400 × 10⁶ = 21.5 × 10⁸ / 4 × 10⁸ = 21.5 / 4 = 5.375 gallons/personTo find how many gallons of fruit juice would your class consume multiply the average consumption by the number of your class mates.
Please help I'm not sure what should I substitute the variable (x) by
Answers
From the given table, the quadratic model is given by
[tex]y=1.2x^2+13x+504.3[/tex]which corresponds to option B.
The general quadratic model is given by
[tex]y=Cx^2+Bx+A[/tex]and we need to find the constants A, B and C. They are given by
and
For instance, the variance for x, denoted by S_xx is given by
[tex]S_{x\times}=(0-20)^2+(10-20)^2+(20-20)^2+(30-20)^2+(40-20)^2[/tex]where x is the variable which corresponds to the "years since 1970" and the number 20 in each parenthesis is the mean of the this variable, that is
[tex]\bar{x}=\frac{0+10+20+30+40}{5}=20[/tex]Now, the variance S_xy is given by