Let x, y, and z be the amounts (in liters, L) of the 25%, 35%, and 55% solutions that the chemist used.
She ended up with 120 L of solution, so
x + y + z = 120 … … … [1]
x L of 25% acid solution contains 0.25x L of acid. Similarly, y L of 35% solution contains 0.35y L of acid, and z L of 55% solution contains 0.55z L of acid. The concentration of the new solution is 40%, so that it contains 0.40 (120 L) = 48 L of acid, which means
0.25x + 0.35y + 0.55z = 48 … … … [2]
Lastly,
z = 3y … … … [3]
since the chemist used 3 times as much of the 55% solution as she did the 35% solution.
Substitute equation [3] into equations [1] and [2] to eliminate z :
x + y + 3y = 120
x + 4y = 120 … … … [4]
0.25x + 0.35y + 0.55 (3y) = 48
0.25x + 2y = 48 … … … [5]
Multiply through equation [5] by -2 and add that to [4] to eliminate y and solve for x :
(x + 4y) - 2 (0.25x + 2y) = 120 - 2 (48)
0.5x = 24
x = 48
Solve for y :
x + 4y = 120
4y = 72
y = 18
Solve for z :
z = 3y
z = 54
During a particularly dry growing season in a southern state, farmers noticed that there is a delicate balance between the number of seeds that are planted per square foot and the yield of the crop in pounds per square foot. The yields were the smallest when the number of seeds per square foot was either very small or very large.
What is the explanatory variable for this relationship?
yield of the crop
location of the farm
precipitation for the growing season
number of seeds planted per square foot
I think it's (D).
number of seeds planted per sf
Answer:
The guy above me is correct
Step-by-step explanation:
2022
Answer:
number of seeds planted per square foot
Step-by-step explanation:
response is the yield explained by how many seeds are planted
find the sum 38+39+40+41...+114+115
It seems like you want to find the sum of 38 to 115:
[tex] \displaystyle \large{38 + 39 + 40 + 41 + ... + 114 + 115}[/tex]
If we notice, this is arithmetic series or the sum of arithmetic sequences.
To find the sum of the sequences, there are three types of formulas but I will demonstrate only one and the best for this problem.
[tex] \displaystyle \large{S_n = \frac{n(a_1+a_n) }{2} }[/tex]
This formula only applies to the sequences that have the common difference = 1.
Given that a1 = first term of sequence/series, n = number of terms and a_n = last term
We know the first term which is 38 and the last term is 115. The problem here is the number of sequences.
To find the n, you can use the following formula.
[tex] \displaystyle \large{n = (a_n - a_1) + 1}[/tex]
Substitute an = 115 and a1 = 38 in the formula of finding n.
[tex] \displaystyle \large{n = (115 - 38) + 1} \\ \displaystyle \large{n = (77) + 1} \\ \displaystyle \large{n = 78}[/tex]
Therefore the number of sequences is 78.
Then we substitute an = 115, a1 = 38 and n = 78 in the sum formula.
[tex] \displaystyle \large{S_{78} = \frac{78(38+115) }{2} } \\ \displaystyle \large{S_{78} = \frac{39(38+115) }{1} } \\ \displaystyle \large{S_{78} = 39(153) } \\ \displaystyle \large \boxed{S_{78} = 5967}[/tex]
Hence, the sum is 5967.
At a time hours after taking a tablet, the rate at which a drug is being eliminated r(t)= 50 (e^-01t - e^-0.20t)is mg/hr. Assuming that all the drug is eventually eliminated, calculate the original dose.
Answer:
2500 mg
Step-by-step explanation:
Since r(t) is the rate at which the drug is being eliminated, we integrate r(t) with t from 0 to ∞ to find the original dose of drug, m. Since all of the drug will be eliminated at time t = ∞.
Since r(t) = 50 (e^-01t - e^-0.20t)
m = ∫₀⁰⁰50 (e^-01t - e^-0.20t)
= 50∫₀⁰⁰(e^-01t - e^-0.20t)
= 50[∫₀⁰⁰e^-01t - ∫₀⁰⁰e^-0.20t]
= 50([e^-01t/-0.01]₀⁰⁰ - [e^-0.20t/-0.02]₀⁰⁰)
= 50(1/-0.01[e^-01(∞) - e^-01(0)] - {1/-0.02[e^-0.02(∞) - e^-0.02(0)]})
= 50(1/-0.01[e^-(∞) - e^-(0)] - {1/-0.02[e^-(∞) - e^-(0)]})
= 50(1/-0.01[0 - 1] - {1/-0.02[0 - 1]})
= 50(1/-0.01[- 1] - {1/-0.02[- 1]})
= 50(1/0.01 - 1/0.02)
= 50(100 - 50)
= 50(50)
= 2500 mg
Use the discriminant to determine the number of solutions to the quadratic equation −40m2+10m−1=0
From the analysis of the discriminant, you obtain that the quadratic function has no real solutions.
In first place, you must know that the roots or solutions of a quadratic function are those values of x for which the expression is 0. This is the values of x such that y = 0. That is, f (x) = 0.
Being the quadratic function f (x)=a*x² + b*x + c, then the solution must be when: 0 =a*x² + b*x + c
The solutions of a quadratic equation can be calculated with the quadratic formula:
[tex]Solutions=\frac{-b+-\sqrt{b^{2} -4*a*c} }{2*a}[/tex]
The discriminant is the part of the quadratic formula under the square root, that is, b² - 4*a*c
The discriminant can be positive, zero or negative and this determines how many solutions (or roots) there are for the given quadratic equation.
If the discriminant:
is positive: the quadratic function has two different real solutions. equal to zero: the quadratic function has a real solution. is negative: none of the solutions are real numbers. That is, it has no real solutions.In this case, a= -40, b=10 and c= -1. Then, replacing in the discriminant expression:
discriminant= 10² -4*(-40)*(-1)
Solving:
discriminant= 100 - 160
discriminant= -60
The discriminant is negative, so the quadratic function has no real solutions.
Solve this inequality: x+ 4< 16
Answer:
x < 12
Step-by-step explanation:
subtract 4 from both sides:
x + 4 < 16
- 4 -4
x < 12
Answer:
x<4
Step-by-step explanation:
x+4 <16
x < 16
4
x<4
I hope this will help you
Will give brainliest
mplete the equation describing how
x and y are related.
Х
0 1
2
3
4
Y -1 3 7
11 15
y = 4x + [? ]
Enter the answer that belongs in [?]
Answer:
y = 4x + -1
Step-by-step explanation:
clearly seen.
what is the volume of the container
Please help me to find this answer
Answer:
37
Step-by-step explanation:
Tan(B) = 6/8
B= arctan(3/4)=37
(-2x) (x-3) answer please
Answer:
−2x^2+6x
Explanation:
You just have to distribute meaning you have to multiply -2x to the equation.
Hello I'm new can anyone help me with this question?
Thank you so much! <3 xoxo
Does the function ƒ(x) = (1∕2) + 25 represent exponential growth, decay, or neither?
A) Exponential growth
B) Impossible to determine with the information given.
C) Neither
D) Exponential decay
Answer:
A) Exponential growth
Step-by-step explanation:
The profit earned by a hot dog stand is a linear function of the number of hot dogs sold. It costs the owner $48 dollars each morning for the day’s supply of hot dogs, buns and mustard, but he earns $2 profit for each hot dog sold. Which equation represents y, the profit earned by the hot dog stand for x hot dogs sold? y=48x−2 y=48x+2 y=2x−48 y=2x+48
Answer:
c. y=2x−48
Explanation:
It is telling us that it costs $48 each morning to buy the day's supply of hot dogs, so we must subtract that from our pay, and it will be our y intercept
It also says he earns $2 per hot dog, so that will be our slope (rate of change)
Hope it helps! :]
y = 2x - 48 equation represents the profit earned by the x hot dog sold.
What is linear equation?A linear equation is an algebraic expression in which highest power of the given variable is equals to one.
Given that, the profit earned by a hot dog stand is a linear function of the number of hot dogs sold.
It costs the owner $48 dollars each morning for the day’s supply of hot dogs, buns and mustard, but he earns $2 profit for each hot dog sold.
We need to establish an equation that represents the total profit,
According to the question,
x represents the number of hot dogs sold
y represents the total profit earned
Cost required for supply = $48
Profit on each hot dog sold = $2
As per the condition given, the required linear equation is =
y = 2x - 48
Hence, y = 2x - 48 equation represents the profit earned by the x hot dog sold.
Learn more about linear equation here :
brainly.com/question/11897796
#SPJ7
The sum of the interior angles of a regular nonagon (9-gon) is equal to
The sum of the interior angles is 1260°
Question 3 plz show ALL STEPS
Answer:
7,0, -1 and -2
Step-by-step explanation:
Just substitute the values,
a. f(g(7))=f(-1) [g(7)=-1 given]
=7 [f(-1)=7 given]
b.f(g(-1))=f(3)=0 [g(-1)=3 Given]
c.g(f(-1))=g(7)=-1 [f(-1)=7 given]
d.g(f(7))=g(5)=-2 [f(7)=g(5) given]
Which expression is equivalent to (b^n)m?
Step-by-step explanation:
By the law of exponent :
(a^n)^m=a^n×m
Option C
b^n×m is the correct answer...
hope it helps
Which of the following show the factored equivalent of
f(x) = (2x^2 +7x + 3)(x - 3) and its zeros?
Answer:
the answer is "D"
(2x+1)(x+3)(x-3) //// -3,-.5,3
Step-by-step explanation:
Factored Form: y= (2x+1)(x+3)(x-3)
Answer:
D
Step-by-step explanation:
[tex]f(x) = (2x^2 +7x + 3)(x - 3)[/tex] is factored into: [tex]f(x)= (2x+1)(x+3)(x-3)[/tex]
That takes out the choices B and C.
The roots are -0.5, 3, and -3.
Therefore, the answer is D.
I hope this helps!
pls ❤ and mark brainliest pls!
If f(x) = x2 + 9x – 14 and g(x) = x2 – x + 3, find (f – g)(x).
Answer:
10x-17
Step-by-step explanation:
f(x) = x^2 + 9x – 14
g(x) = x^2 – x + 3
(f – g)(x)=x^2 + 9x – 14 - (x^2 – x + 3)
Distribute the minus sign
(f – g)(x)=x^2 + 9x – 14 - x^2 + x - 3
Combine like terms
=10x-17
If you double then triple a number, this is the same as cutting the number in half. What is the number?
9514 1404 393
Answer:
zero
Step-by-step explanation:
3(2x) = x/2
5.5x = 0 . . . . subtract x/2
x = 0 . . . . . . . divide by 5.5
The number is zero.
I need help please
Don’t skip the questions if you know the answer please I need the answers as soon as possible!!
y=x²-10x-7
a>0 so we will be looking for minimum
x=-b/2a=10/2=5
y=25-50-7=-32
Answer: (5;32)
y=-4x²-8x+1
а<0 so we will be looking for maximum
х=-b/2a=8/-8=-1
у=4+8+1=13
Maximum point (-1;13)
For the following function, solve both f'(x) = 0 and f''(x) = 0 for x.
f(x) = x(x - 3)^4
I need help plz!!
8.57396817...•5/8 is rational or irrational?
Answer:
Irrational
Step-by-step explanation:
Any non-zero rational number multiplied by an irrational number will be irrational. We can rewrite this as (8.57... * 5) / 8, but we have no idea how to make 8.57... * 5 rational, or expressed as the quotient of two integers.
point slope of the line equation, slope=4, passing through(7,2)
Answer:
Step-by-step explanation:
Point-slope equation for line of slope m that passes through (x₀, y₀):
y-y₀ = m(x-x₀)
apply your data
y-2 = 4(x-6)
Answer:
y−2= −2(x−7)
Step-by-step explanation:
khan academy says its right
consider a study conducted to determine the average protein intake among an adult population. Suppose that a confidence level of 85% is required with an interval about 10 units wide. if a preliminary data indicates a standard deviation of 20g, what sample of adults should be selected for the study?
Answer:
made up of about 20 common amino acids. The proportion of these amino acids varies as a characteristic of a given protein, but all food proteins—with the exception of gelatin—contain some of each. Amino nitrogen accounts for approximately 16% of the weight of proteins. Amino acids are required for the synthesis of body protein and other important nitrogen-containing compounds, such as creatine, peptide hormones, and some neurotransmitters. Although allowances are expressed as protein, a the biological requirement is for amino acids.
Proteins and other nitrogenous compounds are being degraded and resynthesized continuously. Several times more protein is turned over daily within the body than is ordinarily consumed, indicating that reutilization of amino acids is a major feature of the economy of protein metabolism. This process of recapture is not completely efficient, and some amino acids are lost by oxidative catabolism. Metabolic products of amino acids (urea, creatinine, uric acid, and other nitrogenous products) are excreted in the urine; nitrogen is also lost in feces, sweat, and other body secretions and in sloughed skin, hair, and nails. A continuous supply of dietary amino acids is required to replace these losses, even after growth has ceased.
Amino acids consumed in excess of the amounts needed for the synthesis of nitrogenous tissue constituents are not stored but are degraded; the nitrogen is excreted as urea, and the keto acids left after removal of the amino groups are either utilized directly as sources of energy or are converted to carbohydrate or fat.
Subtract.
7x2 - 5x+3
(2x² + 7x-4)
Answer:
7×=14
5×3=15
5+3=8
7×4=28
7-4=3
2×2=4
if add this all will get the answer as 72
if we will subtraction answer will be as -44
Step-by-step explanation:
so we will get the answer asaddition = 72
subtraction= -44
so this is the answerplease give me points
Find the equation of the tangent line at the point (0,1) of the graph of the function f(x) = x^3 - 2x + 1 ?
9514 1404 393
Answer:
y = -2x +1
Step-by-step explanation:
The derivative of the function is ...
f'(x) = 3x^2 -2
so the slope at x=0 is f'(0) = -2. In slope-intercept form, the equation of the tangent line is ...
y = -2x +1
prove that tan² theta + cot² theta = sec² theta cosec² theta- 2
Step-by-step explanation:
Tan² theta = sec² theta - 1
Cot² theta = cosec² theta - 1
Tan²+Cot² = sec²-1+cosec²-1
= sec²+cosec²-2
Please find attached herewith the solution of your question.
If you have any doubt, please comment.
According to the U.S. National Center for Health Statistics, there is a 98% probability that a
20-year-old male will survive to age 30.
(a) Using statistical software, simulate taking 100 random samples of size 30 from this
population.
(b) Using the results of the simulation, compute the probability that exactly 29 of the 30 males
survive to age 30.
(c) Compute the probability that exactly 29 of the 30 males survive to age 30, using the
binomial probability distribution.
(d) Using the results of the simulation, compute the probability that at most 27 of the 30 males
survive to age 30.
(e) Compute the probability that at most 27 of the 30 males survive to age 30 using the
binomial probability distribution.
(f) Compute the mean number of male survivors in the 100 simulations of the probability
experiment. Is it close to the expected value?
(g) Compute the standard deviation of the number of
male survivors in the 100 simulations of the probability experiment. Compare the result to the
theoretical standard deviation of the probability distribution
Answer:
0.03398 or 3.398%
Step-by-step explanation:
-This is a binomial probability problem.
-Given p=0.24, n=100, the probability that exactly 30 people is calculated as:
Hence, the probability that exactly 30 people have hypertension is 0.03398
find the greatest number than divides 45 60 75 without leaving remainder
Answer:
15
Step-by-step explanation:
15 is the greatest number that divides 45 60 75 without leaving remainder
Answer:
15
Step-by-step explanation:
Let write the factors of each number:
45: (1,3,5,9,15,45)
60:(1,2,3,4,5,6,10,12,15,20,30,60)
75:(1,3,5,15,15,75).
The greatest common factor is 15. So the answer is 15.
Find the bases for Col A and Nul A, and then state the dimension of these subspaces for the matrix A and an echelon form of A below.
A= 1 3 8 2 7 1 3 8 2 7
2 7 20 6 20 --- 0 1 4 2 6
-3 -12 -36 -7 -19 0 0 0 1 4
3 13 40 9 25 0 0 0 0 0
Start 4 By 5 Table 1st Row 1st Column 1 2nd Column 3 3rd Column 8 4st Column 2 5st Column 7 2nd Row 1st Column 2 2nd Column 7 3rd Column 20 4st Column 6 5st Column 20 3rd Row 1st Column negative 3 2nd Column negative 12 3rd Column negative 36 4st Column negative 7 5st Column negative 19 4st Row 1st Column 3 2nd Column 13 3rd Column 40 4st Column 9 5st Column 25 EndTable
tilde
Start 4 By 5 Table 1st Row 1st Column 1 2nd Column 3 3rd Column 8 4st Column 2 5st Column 7 2nd Row 1st Column 0 2nd Column 1 3rd Column 4 4st Column 2 5st Column 6 3rd Row 1st Column 0 2nd Column 0 3rd Column 0 4st Column 1 5st Column 4 4st Row 1st Column 0 2nd Column 0 3rd Column 0 4st Column 0 5st Column 0 EndTable
A basis for Col A is given by
StartSet nothing EndSet
(Use a comma to separate vectors as needed.)
The dimension of Col A is
3.
A basis for Nul A is given by
StartSet nothing EndSet
(Use a comma to separate vectors as needed.)
The dimension of Nul A .
Answer:
skip counting by 0
Step-by-step explanation:
skipcount by 0 to get to 100 for the third column.
Answer:
its the first graph
Step-by-step explanation:
I got it right bc im cool like that ig
prove:
sin²A-cos²B=sin²B-cos²A
Step-by-step explanation:
thwashm m GB DC GM 3hka it g feeds ygzdkzyzuzjz indin, mi, hn zbe
Answer:
Solution given:
L.H.S
sin²A-cos²B
we havesin²A=1-cos²A and Cos²B=1-sin²B
nowreplacing value
1-cos²A-(1-sin²B)
open bracket1-cos²A-1+sin²B
keep together like terms1-1+sin²B-Cos²A
=sin²B-Cos²A
R.H.S
proved.