Answer:
x + 5y = 237
5x + 5y = 465
Step-by-step explanation:
Let
x = length of cardio class
y = length of weightlifting class
x + 5y = 237 (1)
5x + 5y = 465 (2)
Using elimination method
Subtract (1) from (2) to eliminate y
5x - x = 465 - 237
4x = 228
x = 228/4
x = 57 minutes
Substitute x = 57 into (1)
x + 5y = 237 (1)
57 + 5y = 237
5y = 237 - 57
5y = 180
y = 180/5
y = 36 minutes
x = length of cardio class = 57 minutes
y = length of weightlifting class = 36 minutes
When an airplane is 35,000 feet from an air traffic control tower, the angle of elevation between the tower and the airplane is.
What is the approximate altitude, a, of the plane at this point?
A. 45,689 feet
B. 26,812 feet
C. 29,369 feet
D. 41,711 feet
Answer:
26,812 ft
Step-by-step explanation:
The drawing given is very helpful in this case. When solving problems like this, it's important to realize what trigonometric ratio we're going to use. From the given angle (50°), we are given the hypotenuse (35,000 ft) and we're trying to solve for the opposite side ([tex]a[/tex]).
So since we're trying to find the opposite side side and we have the hypotenuse, we should try to find a trigonmetric ratio between the opposite side and the hypotenuse. Using SOH-CAH-TOA, hopefully you can see that we should pick SOH (i.e. [tex]\sin(\theta)=\frac{\text{opposite}}{\text{hypotenuse}}[/tex]). Therefore, we can set up our equation given the angle [tex]\theta=50^\circ[/tex].
[tex]\sin(50^\circ)=\frac{a}{35000}[/tex]
Since we're solving for [tex]a[/tex], we can just rearrange to get [tex]a=35000\sin(50^\circ)=26812[/tex]
Therefore, the plane's altitude [tex]a[/tex] is 26,812 ft.
The approximation altitude of the plane at 35,000 feet from an air traffic control tower will be 26812 feet hence option (B) will be correct.
What is a trigonometric function?the trigonometric functions are real functions for only an angle of a right-angled triangle to ratios of two side lengths.
The domain input value for the six basic trigonometric operations is the angle of a right triangle, and the result is a range of numbers.
The trigonometric function is only valid for the right angle triangle and it is 6 functions which are given as sin cos tan cosec sec cot.
Given that 35000 feet are the distance between a plane and the air traffic control tower.
Hypotaneous = 35000 feet
The angle of elevation is 50°
By trigonometric function sin
Sinx = perpendicular/hypotaneous
Sin50° = Altitude/35000
Altitute = 35000 × sin50°
Altitude = 26811.55 ≈ 26812 feet will be the correct answer.
For more information about the trigonometric function
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PLEASE HELP QUICKKKKKKKK
9514 1404 393
Explanation:
Using a random number generator to choose coefficients, we can substitute the required solution to find the constants in the equations. Here is one possible set of equations.
17x +7y +8z = 6
12x -6y +z = -16
14x +8y +11z = 16
__
Additional comment
"Standard form" requires the x-coefficient be positive. Truth be told, the random number generator came up with negative numbers for the first and last equations (on the second try). On the first try, it came up with a couple of zero coefficients. Such is the behavior of random numbers.
The trick with choosing a set of numbers "by hand" is doing it in such a way that the equations are independent.
An engineering consulting firm wanted to evaluate the diameter of rivet heads. The following data represent the diameters (in hundredths of an inch) for a random sample of 25 rivet heads:
(20 pts) 6.81 6.79 6.69 6.59 6.65 6.60 6.74 6.70 6.76 6.84 6.81 6.71 6.66 6.76 6.76 6.77 6.72 6.68 6.71 6.79 6.72 6.72 6.72 6.79 6.83
a. Set up a 95% confidence interval estimate of the average diameter of rivet heads (in hundredths of an inch)
b. Set up a 95% CI estimate of the standard deviation of the diameter rivet heads (in hundredths of an inch)
Answer:
a)CI 95 % = ( 6.7063 ; 6.7593) ( in hundredths of an inch)
b) CI 95 % = ( 0.05 < σ < 0.089 ) ( in hundredths of an inch)
Step-by-step explanation:
From the problem statement, we have a manufacturing process and we we assume a normal distribution, from sample data:
x = 6.7328 and s = 0.0644
a) CI 95 % = ( x ± t(c) * s/√n )
t(c) df = n -1 df = 25 - 1 df = 24
CI = 95 % α = 5 % α = 0.05 α /2 = 0.025
Then from t-student table t(c) = 2.060
s/√n = 0.0644/ √ 25 s/√n = 0.01288
CI 95 % = ( x ± t(c) * s/√n ) = ( 6.7328 ± 2.060*0.01288)
CI 95 % = ( 6.7328 ± 0.02653 )
CI 95 % = ( 6.7063 ; 6.7593) ( in hundredths of an inch)
b) CI 95 % of the variance is:
CI 95 % = ( ( n - 1 ) * s² / χ²₁ - α/₂ ≤ σ² ≤ ( n - 1 )*s² / χ²α/₂ )
( n - 1 ) * s² = ( 25 - 1 ) * (0.0644)² = 24* 0.00414
( n - 1 ) * s² = 0.09936
And from χ² table we look for values of
χ² α/₂ ,df df = 24 and α/2 = 0.025
χ² (0.025,24) = 12.40 and χ²₁ - α/₂ = χ² (0.975, 24)
χ² (0.975, 24) = 39.36
Then
CI 95 % = ( 0.09936 / 39.36 ≤ σ² ≤ 0.09936 / 12.40)
CI 95 % = ( 0.0025 ≤ σ² ≤ 0.0080)
Then for the standard deviation, we take the square root of that interval
CI 95 % = ( 0.05 < σ < 0.089 )
Perimeter of a 14cm,10cm,6cm and 20cm shape?
Answer:
The perimeter is 50 cm.
Step-by-step explanation:
P= 14 + 10 + 6 + 20= 50 cm
A cone has a height of 3 feet. The diameter of the base is 8 feet. What is the approximate volume of the cone in feet to the nearest hundreth?
Answer:
12.56 feet cubed
Step-by-step explanation:
Diameter of 8= radius of 4
4 x 3.14=12.56
12.56x3=37.68
37.68/3=12.56
Write the expression. Then, complete the statements.
twice the difference of a number and seven
The word "twice" means multiplication by 2 v
The words "the difference of indicate
put these numbers in order of size, smallest to largest 4.5,-1,-3,-3.5,3
Answer:
-3.5, -3, -1, 3, 4.5
Step-by-step explanation:
Answer:
-3.5, -3, -1, 3, 4.5 because the higher the negative is, the lower the number.
How many ways can a person toss a coin 16 times so that the number of heads is between 7 and 14 inclusive
50626 ways with a probability of 0.77
Step-by-step explanation:If a coin is tossed once, there are two possible results - a head or a tail. i.e 2¹ = 2
If the coin is tossed twice, there are four possible results - 4 heads no tail, 4 tails no head, 1 head 3tails or 2 heads 2 tails. That is 2² = 4
If the coin is tossed thrice, there are eight possible results. That is 2³ = 8.
Now, if the coin is tossed 16 times, there are 2¹⁶ = 65536 likely results.
From these 16 tosses, let's calculate the number of ways of achieving or selecting 7, 8, 9, 10, 11, 12, 13 or 14 heads. We use the combination formula given as follows;
Cₙ, ₓ = n! ÷ [ (n-x)! (x)! ]
Where;
n = number of tosses
x = number of selection
number of ways of getting 7 heads;
n = 16
x = 7
=> C₁₆, ₇ = 16! ÷ [ (16-7)! (7)! ]
=> C₁₆, ₇ = 16! ÷ [ (9)! (7)! ]
=> C₁₆, ₇ = 11440
number of ways of getting 8 heads;
n = 16
x = 8
=> C₁₆, ₈ = 16! ÷ [ (16-8)! (8)! ]
=> C₁₆, ₈ = 16! ÷ [ (8)! (8)! ]
=> C₁₆, ₈ = 12870
number of ways of getting 9 heads;
n = 16
x = 9
=> C₁₆, ₉ = 16! ÷ [ (16-9)! (9)! ]
=> C₁₆, ₉ = 16! ÷ [ (7)! (9)! ]
=> C₁₆, ₉ = 11440
number of ways of getting 10 heads;
n = 16
x = 10
=> C₁₆, ₁₀ = 16! ÷ [ (16-10)! (10)! ]
=> C₁₆, ₁₀ = 16! ÷ [ (6)! (10)! ]
=> C₁₆, ₁₀ = 8008
number of ways of getting 11 heads;
n = 16
x = 11
=> C₁₆, ₁₁ = 16! ÷ [ (16-11)! (11)! ]
=> C₁₆, ₁₁ = 16! ÷ [ (5)! (11)! ]
=> C₁₆, ₁₁ = 4368
number of ways of getting 12 heads;
n = 16
x = 12
=> C₁₆, ₁₂ = 16! ÷ [ (16-12)! (12)! ]
=> C₁₆, ₁₂ = 16! ÷ [ (4)! (12)! ]
=> C₁₆, ₁₂ = 1820
number of ways of getting 13 heads;
n = 16
x = 13
=> C₁₆, ₁₃ = 16! ÷ [ (16-13)! (13)! ]
=> C₁₆, ₁₃ = 16! ÷ [ (3)! (13)! ]
=> C₁₆, ₁₃ = 560
number of ways of getting 14 heads;
n = 16
x = 14
=> C₁₆, ₁₄ = 16! ÷ [ (16-14)! (14)! ]
=> C₁₆, ₁₄ = 16! ÷ [ (2)! (14)! ]
=> C₁₆, ₁₄ = 120
Therefore, the total number of ways of achieving 7, 8, 9, 10, 11, 12, 13 or 14 heads is the sum of the results above. i.e
11440 + 12870 + 11440 + 8008 + 4368 + 1820 + 560 + 120 = 50626 ways
P(getting number of heads between 7 and 14 inclusive) = [number of ways of achieving 7, 8, 9, 10, 11, 12, 13 or 14 ] ÷ [total number of possible outcomes]
= [tex]\frac{50626}{65536}[/tex]
= 0.77
Which of the following statistics would provide a good comparison between data sets?
Group of answer choices
all of these
correlation
interquartile range
mean
The following statistics which would provide a good comparison between data sets is all of the above and is denoted as option A.
What is Statistics?This refers to the branch of science which involves the collection and interpretation of data sets or variables. There are different ways or techniques which are used and they vary according to the features of the data set.
There are statistics which provide a good comparison between data sets include the following below:
correlationinterquartile rangemeanThis comparison is done so as to to prove that there are no differences between them and other reasons.
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Which expression can be used to convert 22 Australian dollars to US dollar
Answer:26.4
Step-by-step explanation:1.2 x22
You and your family are planning a roadtrip. You determine that the distance you need to drive is 660 miles and that you can average 60 miles per hour for the entire trip. How many hours will your trip take?
Answer:
11 hours
Step-by-step explanation:
Find how many hours the trip will take by dividing the number of miles by the rate in miles per hour:
660/60
= 11
So, the trip will take 11 hours
Given g(x) -x + 4, solve for a when g(x) = 8.
Answer:
x = 12
Step-by-step explanation:
g(x) - × + 4 =0
put g(x) = 8
so, 8 - x + 4 = 0
x = 12
Answer:
x = - 4
Step-by-step explanation:
Given g(x) = - x + 4 and g(x) = 8 , the equate the right sides, that is
- x + 4 = 8 ( subtract 4 from both sides )
- x = 4 ( multiply both sides by - 1 )
x = - 4
Sea grass grows on a lake. The rate of growth of the grass is ????????/???????? = ????????, where ???? is a constant.
a. Find an expression for ????, the amount of grass in the lake (in tons), in terms of ????, the number of years, if the amount of grass is 100 tons initially, and 120 tons after one year.
b. In how many years will the amount of grass available be 300 tons?
c. If fish are now introduced into the lake and consume a consistent 80 tons/year of sea grass, how long will it take for the lake to be completely free of sea grass?
Answer:
[tex](a)\ G(t) = 100 *e^{0.1823t}[/tex]
[tex](b)\ t = 6[/tex]
[tex](c)\ t = 1.7[/tex]
Step-by-step explanation:
Given
[tex]G_0 = 100[/tex] --- initial
[tex]G(1) = 120[/tex] --- after 1 year
[tex]r \to rate[/tex]
Solving (a): The expression for g
Since the rate is constant, the distribution of G follows:
[tex]G(t) = G_0 * e^{rt}[/tex]
[tex]G(1) = 120[/tex] implies that:
[tex]G(t) = G_0 * e^{rt}[/tex]
[tex]120 = G_0 * e^{r*1}[/tex]
Substitute [tex]G_0 = 100[/tex]
[tex]120 = 100 * e^{r[/tex]
Divide both sides by 100
[tex]1.2 = e^{r[/tex]
Take natural logarithm of both sides
[tex]\ln(1.2) = \ln(e^r)[/tex]
[tex]0.1823 = r[/tex]
[tex]r = 0.1823[/tex]
So, the expression for G is:
[tex]G(t) = G_0 * e^{rt}[/tex]
[tex]G(t) = 100 *e^{0.1823t}[/tex]
Solving (b): t when G(t) = 300
We have:
[tex]G(t) = 100 *e^{0.1823t}[/tex]
[tex]300 = 100 *e^{0.1823t}[/tex]
Divide both sides by 100
[tex]3 = e^{0.1823t}[/tex]
Take natural logarithm
[tex]\ln(3) = \ln(e^{0.1823t})[/tex]
[tex]1.099 = 0.1823t[/tex]
Solve for t
[tex]t = \frac{1.099}{0.1823}[/tex]
[tex]t = 6[/tex] --- approximated
Solving (c): When there will be no grass
Reduction at a rate of 80 tons per year implies that:
[tex]G(t) = 100 *e^{0.1823t}- 80t[/tex]
To solve for t, we set G(t) = 0
[tex]0 = 100 *e^{0.1823t}- 80t\\[/tex]
Rewrite as
[tex]80t = 100 *e^{0.1823t}[/tex]
Divide both sides by 100
[tex]0.8t = e^{0.1823t}[/tex]
Take natural logarithm of both sides
[tex]\ln( 0.8t) = \ln(e^{0.1823t})[/tex]
[tex]\ln( 0.8t) = 0.1823t[/tex]
Plot the graph of: [tex]\ln( 0.8t) = 0.1823t[/tex]
[tex]t = 1.7[/tex]
Find the quotient of 4x^3-12x² + 8x/ - 4x
O x2 + 3x - 2
O x²-12x + 4
O -x2 – 3x + 2
O x² + 12x - 4
Answer:
-x^2+3x-2
Step-by-step explanation:
I think one of the signs are wrong in the equation.
What is the difference of the polynomials?
(5x^3 + 4x^2) - (6x^2 - 2x - 9)
Answers:
A.) -x^3 + 6x^2 + 9
B.) -x^3 + 2x^2 - 9
C.) 5x^3 - 2x^2 - 2x - 9
D.) 5x^3 - 2x^2 + 2x + 9
Answer:
D
Step-by-step explanation:
We want to find the difference between the two polynomials:
[tex](5x^3+4x^2)-(6x^2-2x-9)[/tex]
Distribute the negative:
[tex]=(5x^3+4x^2)+(-6x^2+2x+9)[/tex]
Rearrange the terms:
[tex]=(5x^3)+(4x^2-6x^2)+(2x)+(9)[/tex]
Combine like terms. Hence:
[tex]=5x^3-2x^2+2x+9[/tex]
Our answer is D.
An angle measures. What is the measure of its complement? (b) An angle measures 48 . What is measure 26 of its supplement?
Adam tabulated the values for the average speeds on each day of his road trip as 60.5, 63.2, 54.7, 51.6, 72.3, 70.7, 67.2, and 65.4 mph. The sample standard deviation is 7.309.Select the 98% confidence interval for Adam’s set of data.a. 46.94 to 71.33b. 46.94 to 79.46c. 55.45 to 79.46d. 55.45 to 70.95
Answer:
Option D, 55.45 to 70.95
Step-by-step explanation:
Alpha = 1 – confidence interval
Alpha = 1 – 0.98 = 0.02
Sample size = n = 8
t (alpha/2) ; (n-1) = t (0.02/2) ; (8-1) = t 0.01, 7 = 2.998
Mean = sum of all frequencies /total number of frequency = 505.6/8 = 63.2
s = 7.309
E = t (0.01;7) * s/sqrt n
Substituting the given values, we get –
E = 2.998 * 7.309 /sqrt (8)
E = 7.75
98% confidence interval
Mean – E and Mean + E
63.2 – 7.75 and 63.2 + 7.75
(55.45, 70.95)
Answer: 55.45 to 70.95
Step-by-step explanation:
Time (hours) 3.2, 4.8, 7.2, t, 12.4
Distance (miles) 80, 120, 180, 245, t
Answer:
t=2 plz mark me as brainliest
Step-by-step explanation:
the solution set for -2x[tex]-2x^{2}+12x=0[/tex]
A sample of students at a university took a test that diagnosed their learning styles as active or reflective and also as visual or verbal. Each student received a numerical score on the active/reflective style and also a numerical score on the visual/verbal style. The sample size was 39, and the sample correlation coefficient turned out to equal .273.a. State the hypotheses for testing whether there is a positive correlation between these variables in the population of all students at this university.b. Calculate the value of the test statistic.c. Determine the p-value as accurately as possible.d. State the test decision for the α= .10 and α= .05 significance levels, and summarize your conclusion in context.e. If the sample size was much larger, and the value of the sample correlation coefficient stayed the same, describe the impact on your test statistic, p-value, and conclusion.
Answer:
Kindly check explanation
Step-by-step explanation:
Given that :
Sample size, n = 39
Correlation Coefficient, r = 0.273
The hypothesis test to examine if there is a positive correlation :
H0 : ρ = 0
If there is a positive correlation, then ρ greater than 1
H0 : ρ > 1
The test statistic :
T = r / √(1 - r²)/(n - 2)
T = 0.273 / √(1 - 0.273²)/(39 - 2)
T = 0.273 / 0.1581541
T = 1.726
The Pvalue using a Pvalue calculator can be be obtained using df = n - 2, df = 39 - 2 = 37
The Pvalue = 0.0463
α= .10 and α= .05
At α= .10
Pvalue < α ; Hence, we reject H0 and conclude that a positive correlation exists
At α= 0.05 ;
Pvalue < α ; Hence, we reject H0 and conclude that a positive correlation exists
A small town experienced explosive population increase. Originally the town had population 170. Within 3 years, the town's population increased by 400%. What's the town's current population
Answer:
850
Step-by-step explanation:
Given that :
Initial population = 170
Percentage rise in population within 3 years = 400%
Hence, the current population of the town will be ;
Current population = Initial population * (1 + rate)
Current population = 170(1 + 400%)
Current population = 170(1 + 4)
Current population = 170(5)
Current population = 850
Sarah bought a TV for £250
Three years later she sold it for £180
Work out her percentage loss
Answer:
36%
Step-by-step explanation:
Step-by-step explanation:
Loss percentage= loss/cost× 100%
250-180=70
70/180=0.3888
0.3888×100%=39%
Factor completely, then place the factors in the proper location on the grid. x2 - 8x + 16
Answer:
( − 4 ) 2
Step-by-step explanation:
2 − 8 + 1 6
2 -4 − 4 + 1 6
x(x-4)-4(x-4)
(x-4)(x-4)
(x-4)2
which can be also written as x-4=0
x=4
A health clinic dietician is planning a meal consisting of three foods whose ingredients are summarized as follows: One Unit ofFood I Food II Food IIIUnits of Protein 10 15 20Units of Carbohydrates 1 2 1Units of Iron 4 8 11Calories 80 120 100The dietician wishes to determine the number of units of each food to use to create a balanced meal containing at least 40 units of protein, 6 units of carbohydrates, and 12 units of iron, and with as few calories as possible. Use solver to find how many units of each food should be used in order to minimize calories.
Answer:
z (min) = 360 x₁ = x₃ = 0 x₂ = 3
Step-by-step explanation:
Protein Carbohydrates Iron calories
Food 1 (x₁) 10 1 4 80
Food 2 (x₂) 15 2 8 120
Food 3 (x₃) 20 1 11 100
Requirements 40 6 12
From the table we get
Objective Function z :
z = 80*x₁ + 120*x₂ + 100*x₃ to minimize
Subjet to:
Constraint 1. at least 40 U of protein
10*x₁ + 15*x₂ + 20*x₃ ≥ 40
Constraint 2. at least 6 U of carbohydrates
1*x₁ + 2*x₂ + 1*x₃ ≥ 6
Constraint 3. at least 12 U of Iron
4*x₁ + 8*x₂ + 11*x₃ ≥ 12
General constraints:
x₁ ≥ 0 x₂ ≥ 0 x₃ ≥ 0 all integers
With the help of an on-line solver after 6 iterations the optimal solution is:
z (min) = 360 x₁ = x₃ = 0 x₂ = 3
A school principal wants to know more about the number of students absent each day. He counts the number of students absent each day for one week: {24, 18, 31,
Answer:
6.27
Step-by-step explanation:
We are to obtain the standard deviation of the given values :
{24, 18, 31,25, 34}
The standard deviation = √(Σ(x - mean)²/ n)
The mean = (ΣX) /n
Using calculator to save computation time :
The standard deviation, s = 6.27 (2 decimal places)
Consider the following statement. For every integer m, 7m + 4 is not divisible by 7. Construct a proof for the statement by selecting sentences from the following scrambled list and putting them in the correct order. Suppose that there is an integer m such that 7m + 4 is divisible by 7.Subtracting 4m from both sides of the equation gives 7 = 4k − 4m = 4(k − m).By definition of divisibility 4m + 7 = 4k, for some integer k.By definition of divisibility 7m + 4 = 7k for some integer k.Dividing both sides of the equation by 7 results in 4 7 = k − m.Dividing both sides of the equation by 4 results in 7 4 = k − m.But k − m is an integer and 7 4 is not an integer.Suppose that there is an integer m such that 7m + 4 is not divisible by 7.But k − m is an integer and 4 7 is not an integer.Subtracting 7m from both sides of the equation gives 4 = 7k − 7m = 7(k − m).
Answer:
A proof for the statement by selecting the given sentences are as follows;
Suppose there is an integer m such that 7·m + 4 is divisible by 7
By definition of divisibility, 7·m + 4 = 7·k for some integer k
Subtracting 7·m from both sides of the equation gives 4 = 7·k - 7·m = 7·(k - m)
Dividing both sides of the equation by 7 results in 4/7 = k - m
But k - m is an integer and 4/7 is not an integer
Therefore, for every integer m, 7·m + 4 is not divisible by 7
Step-by-step explanation:
The given equation can be expressed as follows;
Where 7·m + 4 is divisible by 7, we have;
7·m + 4 = 7·k
Where 'k' is an integer
We have;
7·m + 4 - 7·m = 4 = 7·k - 7·m
∴ k - m = 4/7, where k - m is an integer
∴ k - m cannot be equal to 4/7, from which we have;
7·m + 4 cannot be divisible by 7.
Pleaseeee help is for today
Answer: a + ( 2a - 7 ) = 41
Explanation:
Let be "a" the Nicci's age and "s" the Nicci's sister.
You know that the sum of Nicci's age and her sister's age is 41. This can be represented with the following equation:
a + 8 = 41
And knowing that Nicci's sister is 7 years less than twice Nicci's age, you can write another equation to represent this:
8 = 2a - 7
Now, substitute the second equation into the first equation in order to find the equation that represents this relationship.
Then, this is:
a + ( 2a - 7 ) = 41
Hope it helps...
3.7 pounds of meat costs $20.35. What is the price per pound?
Answer:
$5.5 per pound of meat
Step-by-step explanation:
$20.35 ÷ 3.7 = $5.50
Hope this is helpful
27. Find the length of the segment LK. (G.CO.C.10)
Show your work! (2pts)
J
1
3x
L
K
X + 6
Click to add speaker notes
Answer:
9
Step-by-step explanation:
the only thing we can say for sure is that JL is splitting the triangle and also its baseline IK in half.
so, both sides of the baseline must be equal :
3x = x + 6
2x = 6
x = 3
=> LK = x + 6 = 3 + 6 = 9
Use the graph of the function to find its domain and range. Write the domain and range in interval notation.
Answer:
Domain = -6 < x < 3
range = -6 < x < -4
Step-by-step explanation:
The domain is the input values along the x-axis. According to the graph, the x values are within the interval;
Domain= -6 < x < 3
The range is the output values along the y-axis. According to the graph, the y values are within the interval;
range = -6 < x < -4
