Answer: Hi!
Let's solve your equation step-by-step.
12x^2 + 54x = −42
Step 1: Subtract -42 from both sides.
12x^2 + 54x − (−42) = − 42 − (−42)
12x^2 + 54x + 42 = 0
Step 2: Factor left side of equation.
6(2x + 7)(x + 1) = 0
Step 3: Set factors equal to 0.
2x + 7 = 0 or x + 1 = 0
You have two answers.
x = −7/2 or x = −1
Hope this helps!
How many odd numbers with 4 different digits, can be formed using the digits 1, 2, 3, 4, 5, 6, 7, 8? (No repetition is allowed)
A. 71
B. 200
C. 210
D. 840
E.1680
Answer:
840 ( D )
Step-by-step explanation:
GIVEN DIGITS : 1,2,3,4,5,6,7,8
Number of odd numbers = 4
Number of even numbers = 4
therefore the number of odd numbers with 4 different digits can be formed by the same way the number of even numbers ( without repetition )
Hence the number of ways odd numbers with 4 different digits = Total number of ways of forming 4 digit numbers / 2
8*7*6*5 = 1680 / 2 = 840 ways
A random sample of 11 students produced the following data, where x is the hours spent per month playing games, and y is the final exam score (out of a maximum of 50 points). The data are presented below in the table of values.
x y
14 46
15 49
16 37
17 42
18 37
19 31
20 25
21 23
22 20
23 15
24 12
What is the value of the intercept of the regression line, b, rounded to one decimal place?
Answer:
b = - 3.7
Step-by-step explanation:
here are the data values:
x y XY X²
14 46 644 196
15 49 735 225
16 37 592 256
17 42 714 289
18 37 666 324
19 31 589 361
20 25 500 400
21 23 483 441
22 20 440 484
23 15 345 529
24 12 288 576
now we are required to find the summation (total) of all values of X, Y, XY and X².
∑X = 209
∑Y = 337
∑XY = 5996
∑X² = 4081
The formular for finding b is given as:
b = n∑XY - (X)(Y) / n∑X² - (∑X)²
= 11(5996) - (209)(337) / 11(4081) - (209)²
= 65956 - 70433 / 44891 - 43681
= -4477/ 1210
= -3.7
The question asked us to find the value of b but we can go further to find the equation of the regression line:
a = ∑Y - b∑X / n
= 337 - (-3.7)(209)/ 11
=1110.3/11
= 100.94
the equation is:
Y = 100.94 - 3.7X
I hope you find my solution useful!
=
Consider a bag of jelly beans that has 30 red, 30 blue, and 30 green jelly beans. a) How many color combinations of 15 beans have at least 6 green beans
Answer:
680
Step-by-step explanation:
Number of red beans = 30
Number of Blue beans = 30
Number of green beans = 30
How many color combinations of 15 beans have at least 6 green beans?
Since at least 6 of the beans must be green,
Then (15 - 6) = 9
Then, the remaining 9 could be either red, blue or green.
Therefore, C(9 + (9 - 1), 3)
C(17, 3) = 17C3
nCr = n! ÷ (n-r)! r!
17C3 = 17! ÷ (17 - 3)! 3!
17C3 = 17! ÷ 14!3!
17C3 = (17 * 16 * 15) / (3 * 2)
17C3 = 4080 / 6
17C3 = 680 ways
Using the combination formula, it is found that there are 17,157,323,000,000,000 color combinations of 15 beans have at least 6 green beans.
The order in which the beans are chosen is not important, hence, the combination formula is used to solve this question.
Combination formula:
[tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by:
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
Th total number of combinations of 15 beans from a set of 30 + 30 + 30 = 90 is:
[tex]C_{90,15} = \frac{90!}{15!75!} = 45795674000000000[/tex]
With less than 6 green, we have:
0 green:
[tex]C_{30,0}C_{60,15} = \frac{60!}{15!45!} = 53194089000000[/tex]
1 green:
[tex]C_{30,1}C_{60,14} = \frac{30!}{1!29!} \times \frac{60!}{14!46!} = 520376960000000[/tex]
2 green:
[tex]C_{30,2}C_{60,13} = \frac{30!}{2!28!} \times \frac{60!}{13!47!} = 2247585600000000[/tex]
3 green:
[tex]C_{30,3}C_{60,12} = \frac{30!}{3!27!} \times \frac{60!}{12!48!} = 5681396900000000[/tex]
4 green:
[tex]C_{30,4}C_{60,11} = \frac{30!}{4!26!} \times \frac{60!}{11!49!} = 9391696900000000[/tex]
5 green:
[tex]C_{30,5}C_{60,10} = \frac{30!}{5!25!} \times \frac{60!}{10!50!} = 10744101000000000[/tex]
Hence, the total for the number of combinations with less than 5 green is:
[tex]53194089000000 + 520376960000000 + 2247585600000000 + 5681396900000000 + 9391696900000000 + 10744101000000000 = 28638351000000000[/tex]
Subtracting the total amount of combinations from the number with less than 5 green, the number of combinations with at least 6 green is:
[tex]T = 45795674000000000 - 28638351000000000 = 17157323000000000[/tex]
There are 17,157,323,000,000,000 color combinations of 15 beans have at least 6 green beans.
A similar problem is given at https://brainly.com/question/24437717
find the domain of the graphed function.
The expression $16x^2-106x-105$ can be written as $(8x + a)(2x + b),$ where $a$ and $b$ are integers. What is $a + 2b$?
Answer:
-23
Step-by-step explanation:
16x² - 106x - 105
factoring X
14 x -120 = -1680
14 - 120 = -106
16x² + 14x - 120x - 105
(16x² + 14x) -(120x - 105)
factor out 2 and -15 to get the same expression (8x + 7)
2x(8x + 7) - 15(8x + 7)
(8x + 7)(2x - 15)
a = 7
b = -15
a + 2b
7 + (-15 x 2)
7 + (-30)
= -23
Open the graphing tool. Move the slider for the equation y = kx3 to a position of your choice, where k ≠ 1. Next, move the slider of y = (kx)3 so the two graphs lie on top of one another. How do the values of k compare with one another in this situation? Why do you think that is?
Answer:
For the functions to coincide, the value of k in y = (kx)3 must be smaller than in y = kx3. This is because the value of y changes more rapidly when k is cubed inside the parentheses. The behavior of the functions is similar since a vertical stretch is similar to a horizontal compression.
Step-by-step explanation:
PLATO
which expression is equivalent to(x²y)³?
Answer:
x^6 y^3
Step-by-step explanation:
(x²y)³
We know that (ab) ^c = a^c * b^c
(x²y)³ = x^2 ^3 * y^3
We know that a^b^c = a^(b*c)
(x²y)³ = x^2 ^3 * y^3 = x^( 2*3) y^3 = x^6 y^3
2. A 10 Mg truck hauls a 20 Mg trailer. If the unit starts from rest on a level road with a
tractive force of 20 kN between the driving wheels of the truck and the road, calculate the
acceleration of the unit and the tension in the horizontal draw-bar.
Drawbar
20 Mg Trailer
10 Mg Truck
a=0.667 m/s2
T= 13.3 KN
Oro
W
Answer:
The acceleration on the unit is 0.667 m/s^2
The tension on the draw-bar is 13.34 kN
Step-by-step explanation:
The mass of the truck = 10 Mg = 10 x 10^3 kg
The mass of the trailer = 20 Mg = 20 x 10^3 kg
Tractive force from the truck = 20 kN = 20 x 10^3 N
The total mass of the unit = 10 Mg + 20 Mg = 30 Mg = 30 x 10^3 kg
The tractive force on the unit will produce an acceleration that is given as
F = ma
where
F is the tractive = 20 x 10^3 N
m is the mass of the unit = 30 x 10^3 kg
a is the acceleration of the unit = ?
substituting into the equation
20 x 10^3 = 30 x 10^3 x a
a = (20 x 10^3)/(30 x 10^3) = 0.667 m/s^2
the tension on the draw-bar T is gotten from considering only the mass that is pulled by the draw-bar which is 20 Mg
The acceleration on the unit = 0.667 m/s^2
The drawn mass = 20 Mg = 20 x 10^3 kg
The tension on the draw bar = ma = 20 x 10^3 x 0.667 = 13340 N
= 13.34 kN
The acceleration is 0.00067m/s^2, while the tension on the horizontal bar is 13.4 N
The given parameters are:
[tex]\mathbf{m = 10Mg}[/tex] -- mass of the truck
[tex]\mathbf{M = 20Mg}[/tex] -- mass of the trailer
[tex]\mathbf{F_T = 20kN}[/tex] --- tractive force
Start by calculating the total mass
[tex]\mathbf{M_T = m + M}[/tex]
So, we have:
[tex]\mathbf{M_T = 10Mg + 20Mg}[/tex]
[tex]\mathbf{M_T = 30Mg}[/tex]
Convert to kilograms
[tex]\mathbf{M_T = 30 \times 10^3kg}[/tex]
[tex]\mathbf{M_T = 30000 kg}[/tex]
Force is calculated as:
[tex]\mathbf{F =ma}[/tex]
So, we have:
[tex]\mathbf{20kN =30000kg \times a}[/tex]
Divide both sides by 30000
[tex]\mathbf{a = 0.00067ms^{-2}}[/tex]
The tension on the horizontal bar (i.e. the 20 Mg trailer) is:
[tex]\mathbf{T=ma}[/tex]
So, we have:
[tex]\mathbf{T=20Mg \times 0.00067ms^{-2}}[/tex]
Rewrite as:
[tex]\mathbf{T=20 \times 10^3 kg \times 0.00067m/s}[/tex]
[tex]\mathbf{T=13.4N}[/tex]
Hence, the acceleration is 0.00067m/s^2, while the tension on the horizontal bar is 13.4 N
Read more about force and acceleration at:
https://brainly.com/question/20511022
Twelve apples cost $2.00. How much will 50 apples cost?
Answer:
$8.33
Step-by-step explanation:
[tex]Solve \:using \: proportion\\\\12\:apples = \$ 2\\50\:apples = \$ x\\Cross \: Multiply\\\\12x = 100\\\\\\\frac{12x}{12} = \frac{100}{12} \\\\x = \$ 8.333[/tex]
Answer:
About $8.33.
Step-by-step explanation:
Write a proportion. Make sure the values line up horizontally:
[tex]\frac{12\text{ apples}}{\$2} =\frac{50\text{ apples}}{\$x}[/tex]
Cross multiply:
[tex]100=12x\\x=25/3\approx\$8.33[/tex]
Find the distance between the points. Give an exact answer and an approximation to three decimal places.
(3.1,0.3) and (2.7. - 4.9)
The exact distance is
(Simplify your answer. Type an exact ans
Answer: sqrt(27.2) =approx 5.215
Step-by-step explanation:
The distance between 2 points can be calculated using Phitagor theorem
L= sqrt( (x1-x2)²+(y1-y2)²)
Where x1, y1 are the coordinates of the first point and x2, y2 are the coordinates of the 2-nd point.
L=sqrt((3.1-2.7)²+(0.3-(-4.9))²)= sqrt(0.4²+5.2²)=sqrt(27.2) - this is exact answer.
sqrt(27.2)=5.21536...=approx 5.215
If f(x)=4x-6 and g(x) vx+2 what is (f*g)(7)
Answer: The value of (f*g)(7) is 66.
Step-by-step explanation:
Given functions: [tex]f(x)= 4x-6\text{ and } g(x)=\sqrt{x+2}[/tex]
Since, product of two functions: [tex](u*v)(x)=u(x)\times v(x)[/tex]
[tex](f*g)(x)=f(x)\times g(x)\\\\=4x-6\times \sqrt{x+2}\\\\\Rightarrow\ (f*g)(x)=(4x-6) \sqrt{x+2}[/tex]
[tex](f*g)(7)=(4(7)-6)\sqrt{7+2}\\\\=(28-6)\sqrt{9}\\\\=22\times 3=66[/tex]
Hence, the value of (f*g)(7) is 66.
The U.S. National Whitewater Center in Charlotte uses a pump station to provide the flow of water necessary to operate the rapids. The pump station contains 7 pumps, each with a capacity to deliver 80,000 gallons per minute (gpm). The water channels and ponds in the facility contain 13 million gallons of water. If the pump station is operating 5 pumps simultaneously, assuming ideal conditions how long will it take to completely pump the volume of the system through the pump station
Answer:
t = 32,5 minutes
Step-by-step explanation:
Volume to fill = 13000000 Gal
5 pumps delivering 80000 gal/min
5 * 80000 = 400000 gal/min
If we divide the total volume by the amount of water delivered for the 5 pumps, we get the required time to fill the volume, then
t = 13000000/ 400000
t = 32,5 minutes
What is the rise over run for the slope -11/9
Answer: 11 down and 9 right
Step-by-step explanation:
Slope IS rise over run where the top number of the fraction (numerator) determines the vertical distance --> positive is up, negative is down
and the bottom number of the fraction (denominator) determines the horizontal distance --> positive is right, negative is left.
Given slope = -11/9
the numerator is -11 so the "rise" is DOWN 11 units
the denominator is 9 so the "run" is RIGHT 9 units
(math and social studies) The two lines are messing me up and I'm not sure
Answer:
2009
Step-by-step explanation:
A deficit would be the least amount coming in (Revenues). and the most going out (Expenditures). So you look for the biggest gap. It appears the gap is largest in 2009.
HELP PLEASE PLEASE :(
Answer:
16
Step-by-step explanation:
It’s a ratio.
x/12=21/28
21x=12*28
21x=336
x=336/21
x=16
Find the standard form of the equation of the ellipse with the given characteristics and center at the origin. Foci: (±7, 0); major axis of length 18
Answer: [tex]\dfrac{x^2}{81}+\dfrac{y^2}{32}=1[/tex]
Step-by-step explanation:
The standard form of equation of ellipse with foci (±c,0) as:
[tex]\dfrac{x^2}{a^2}+\dfrac{y^2}{b^2}=1[/tex]
, where major axis = 2a and minor axis = 2b
Given: Foci: (±7, 0); major axis of length 18
i.e. c= 7 and 2a =18 ⇒a= 9
Also,
[tex]c^2=a^2-b^2\Rightarrow\ b^2= a^2-c^2\\\\\Rightarrow\ b^2={9^2-7^2}={81-49}\\\\\Rightarrow\ b^2=32[/tex]
Put value of [tex]a^2[/tex] and [tex]b^2[/tex] , we get the required equation :
[tex]\dfrac{x^2}{81}+\dfrac{y^2}{32}=1[/tex]
if P(x)=1+6x-5x^2 represents the profit in selling x thousand Boombotix speakers, how many speakers should be sold to maximize profit?
Answer:
600
Step-by-step explanation:
[tex]p(x) = 1 + 6x - 5x^2[/tex]
x max = [tex]-b/2a[/tex]
a = -5
b = 6
-6/2(-5) = 6/10 = 3/5 = .6
.6 thousand = 600
600 speakers should be sold.
Alternatively, you can check the vertex of the parabola formed.
Question
Consider this expression.
4/2² - 6²
Type the correct answer in the box. Use numerals instead of words. For help, see this worked example e.
When a =
-5 and b = 3, the value of the expression is
Submit
Answer:
16
Step-by-step explanation:
4 * sqrt( a^2 - b^2)
Let a = -5 and b =3
4 * sqrt( (-5)^2 - 3^2)
Do the squaring first
4 * sqrt( 25 - 9)
Subtract inside the square root
4 * sqrt( 16)
Take the square root
4 * 4
Multiply 16
Answer:
[tex]\Large \boxed{16}[/tex]
Step-by-step explanation:
[tex]4\sqrt{a^2-b^2 }[/tex]
[tex]\sf Plug \ in \ the \ values \ for \ a \ and \ b.[/tex]
[tex]4\sqrt{-5^2-3^2 }[/tex]
[tex]4\sqrt{25-9 }[/tex]
[tex]4\sqrt{16}[/tex]
[tex]4 \times 4=16[/tex]
If AD=2/3AB, the ratio of the length of BC to the length of DE is A. 1/6 B. 1/4 C. 3/2 D. 3/4
Answer:
The correct answer is c
Step-by-step explanation:
Answer:
C.) 3/2
Explanation:
PLATO
Suppose the following data show the prices of 4 cars with similar characteristics that sold at a recent auction (in thousands of dollars): 6.6, 5, 10.7, 7.3. Calculate the standard deviation of the sample of selling prices. (please express your answer using 2 decimal places)
Answer: 2.40
Step-by-step explanation:
Given: The prices of 4 cars with similar characteristics that sold at a recent auction (in thousands of dollars): 6.6, 5, 10.7, 7.3.
Let x: 6.6, 5, 10.7, 7.3.
n= 4
Mean : [tex]\overline{x}=\dfrac{\sum x}{n}[/tex]
[tex]\Rightarrow\ \overline{x}=\dfrac{6.6+5+10.7+7.3}{4}\\\\=\dfrac{29.6}{4}\\\\=7.4[/tex]
Now , standard deviation = [tex]\sqrt{\dfrac{\sum(x-\overline{x})^2}{n-1}}[/tex]
[tex]=\sqrt{\dfrac{(6.6-7.4)^2+( 5-7.4)^2+( 10.7-7.4)^2+( 7.3-7.4)^2}{4-1}}\\\\=\sqrt{\dfrac{0.64+5.76+10.89+0.01}{3}}\\\\=\sqrt{\dfrac{17.3}{3}}\approx2.40[/tex]
Hence, the standard deviation of the sample of selling prices = 2.40
Solve for X: 1+1*12/80-2+3=56x
Answer:
NOT SURE
Step-by-step explanation:
Find the radius of the circle with equation x^2 + y^2 - 10x - 16y + 53 = 0.
Answer:
radius = 10.5 unitsStep-by-step explanation:
Equation of a circle is given by
x² + y² + 2gx + 2fy + c = 0
To find the radius of the circle we use the formula
[tex]r = \sqrt{ {g}^{2} + {f}^{2} - c } [/tex]
where g and f is the center of the circle
From the question
x² + y² - 10x - 16y + 53 = 0
Comparing with the general equation above we have
2g = - 10 2f = - 16
g = - 5 f = - 8
c = 53
Substitute the values into the above formula
That's
[tex]r = \sqrt{ ({ - 10})^{2} + ( { - 8})^{2} - 53 } [/tex]
[tex]r = \sqrt{100 + 64 - 53} [/tex]
[tex]r = \sqrt{111} [/tex]
We have the final answer as
radius = 10.5 unitsHope this helps you
A researcher measures daily driving distance from college and weekly cost of gas for a group of commuting college students. What kind of correlation is likely to be obtained for these two variables?
Answer:
There is a positive correlation between these two variables.
Step-by-step explanation:
Positive correlation is an association amid two variables in which both variables change in the same direction.
A positive correlation occurs when one variable declines as the other variable declines, or one variable escalates while the other escalates.
As the distance covered by the vehicle increases the amount of gas consumed also increases. Thus, the weekly cost of gas will also increase.
Thus, there is a positive correlation between these two variables.
Suppose we want to choose 6 colors, without replacement, from 14 distinct colors. (a) How many ways can this be done, if the order of the choices matters? (b) How many ways can this be done, if the order of the choices does not matter?
Answer:
(a) 2,162,160
(b) 3,003
Step-by-step explanation:
(a) order matters
You can choose from 14 for the first pick. Then you have 13 left for the second pick. Then you have 12 left for the third pick. Keep going until you have 9 left for the 6th pick. The number when order matters is:
total = 14 * 13 * 12 * 11 * 10 * 9 = 2,162,160
(b) Order does not matter
Start with the same number as above for picking 6 out of 14. Since order does not matter, we divide by the number of ways you can arrange 6 items.
Since there are 6! ways of arranging 6 items,
total = 2,162,160/6! = 3,003
The number of ways when the order matters are 121080960.
The number of ways when order does not matters are 3003.
Given,
Choose 6 colors, without replacement, from 14 distinct colors.
We have to find:
- How many ways can this be done, if the order of the choices matters.
- How many ways can this be done if the order of the choices does not matter.
What are permutation and combination?We use permutation when the order of the arrangements matters.
It is given by:
[tex]^ nP_r[/tex] = n! / r!
We use combination when order does not matter.
It is given by:
[tex]^nC_{r}[/tex] = n! / r! (n-r)!
Find the number of ways when order matters.
We have,
n = 14 and r = 6
[tex]^{14}P_{6}[/tex]
= 14! / 6!
= (14 x 13 x 12 x 11 x 10 x 9 x 8 x 7 x 6!) / 6!
= 4 x 13 x 12 x 11 x 10 x 9 x 8 x 7
= 121080960
Find the number of ways when order does not matter.
We have,
n = 14 and r = 6
[tex]^{14}C_{6}[/tex]
= 14! / 6! 8!
= 14 x 13 x 12 x 11 x 10 x 9 / 6 x 5 x 4 x 3 x 2
= 7 x 13 x 11 x 3
= 3003
Thus,
The number of ways when the order matters are 121080960.
The number of ways when order does not matters are 3003.
Learn more about combination here:
https://brainly.com/question/28134115
#SPJ2
Solve for x: 3(x + 1)= -2(x - 1) + 6.
Answer:
x=1
Step-by-step explanation:
3(x + 1)= -2(x - 1) + 6.
Distribute
3x+3 = -2x+2+6
Combine like terms
3x+3 = -2x+8
Add 2x to each side
3x+3+2x = 8
5x+3 = 8
Subtract 3 from each side
5x =5
Divide by 5
x =1
The cost in dollars y of producing x computer
desks is given by y = 40x + 4000
X
100
200
300
a. Complete the table
y
b. Find the number of computer desks that can be produced for $6200. (Hint: Find x when y = 6200.)
a. Complete the table.
х
100
200
300
y
b. For $6200,_ computer desks can be produced
Answer:
a.
y= 40x +4000
x= 100 --> y= 40(100)+4000= 4000+4000=8000
x=200 --> y= 40(200)+4000= 6000+4000= 10000
x=300 --> y= 40(300)+4000= 12000+4000= 16000
(in $)
b.
y= 40x+4000
6200= 40x+4000
6200-4000= 40x
2200= 40x
2200/40= x
55= x
(in unit)
Step-by-step explanation:
I hope this helps
if u have question let me know in comments ^_^
State the correct polar coordinate for the graph shown:
Answer:
Solution : ( - 5, 5π / 4 )
Step-by-step explanation:
There are four cases to consider here, the first two with respect to r > 0, the second two with respect to r < 0. r is the directed distance from the pole, and theta is the directed angle from the positive x - axis. Let's start by listing coordinates when r is positive. r here is 5 units from the positive x - axis.
( 5, θ ) theta here is between 30 and 60 degrees, so we can say it's about 45 degrees.
( 5, θ ) theta here is the remaining negative side of 360 - 45 = 315. That would make it - 315.
And when r is negative ( r < 0 ),
( - 5, θ ) now the point is going to lie on the ray pointing in the opposite direction of the terminal side of theta. This will be 45 degrees more than 180, or 180 + 45 = 225 degrees.
Right away we know that ( - 5, 225° ) is our solution, we don't have to consider the second case. Converting 225 to radians in terms of π will be 5π / 4 radians, giving us a solution of ( - 5, 5π / 4 ) or option b.
a sheet metal worker earns $26.80 per hour after receiving a 4.5% raise. what was the sheet metal worker's hourly pay before raise? Round your answer to the nearest cent
Answer
$25.59
Step-by-step explanation:
subtract by percentage or you can also do:
100% - 4.5% = 95.5%
95.5% x $26.80 = $25.594
IF ROUNDED: $25.59
Answer:
$25.65
Step-by-step explanation:
Let the original hourly rate be r.
Then 1.045r + $26.80/hr.
Dividing both sides by 1.045, we get:
$26.80/hr
r = ------------------ = $25.65 This was the before-raise pay rate.
1.045
Find the product of the roots of the equation
xl-5x - 36 = 0
Answer:
Step-by-step explanation:
Hello, I assume that you mean
[tex]x^2-5x-36[/tex]
The product is -36.
[tex]x_1 \text{ and } x_2 \text{ are the two roots, we can write}\\\\(x-x_1)(x-x_2)=x^2-(x_1+x_2)x+x_1\cdot x_2[/tex]
So in this example, it means that the sum is 5 and the product is -36.
Thank you
Kelvin wants to know whether he skied without falling more than twice as long as anyone else in his family. His dad tells him that he can check by using the inequality 2f < 223, where f is the time skied in seconds for each person. Plug the values for the time skied by each person into the inequality to find the answer.
Lori 55
Vanessa 265
Devon 172
Celia 112
Arnold 356
Answer:
Kelvin did not skied without falling more than twice as long as anyone else in his family.
Step-by-step explanation:
The inequality representing the event where Kelvin skied without falling more than twice as long as anyone else in his family is:
[tex]2f<223[/tex]
Here 223 is the time for Kelvin.
Check for Lori as follows:[tex]2f<223[/tex]
[tex]2\times 55=110<223[/tex]
Kelvin skied without falling more than twice as long as Lori.
Check for Vanessa as follows:[tex]2f<223[/tex]
[tex]2\times 265=530>223[/tex]
Kelvin skied without falling less than twice as long as Vanessa.
Check for Devon as follows:[tex]2f<223[/tex]
[tex]2\times 172=344>223[/tex]
Kelvin skied without falling less than twice as long as Devon.
Check for Celia as follows:[tex]2f<223[/tex]
[tex]2\times 112=224>223[/tex]
Kelvin skied without falling less than twice as long as Celia.
Check for Arnold as follows:[tex]2f<223[/tex]
[tex]2\times 356=712>223[/tex]
Kelvin skied without falling less than twice as long as Arnold.
Thus, Kelvin did not skied without falling more than twice as long as anyone else in his family.
Answer:
Yes, Kevin skied 2x as long as Lori.
Step-by-step explanation:
Kevin's time was 223 seconds; Lori's time was 110 seconds.
110^2 = 220 or 110 multiplied by 2 equals 220 or 110 x 2 = 220 or
110 * 2 = 220
Thus, Kevin indeed, skied twice as long as Lori.
