Answer:
35
Step-by-step explanation:
Here we see 5 black keys for every 7 white keys.
So the ratio is 5:7
If we need 49 white keys, find the amount we scale the original ratio by:
49/7 = 7
So we are scaling by a factor of 7.
The number of black keys would be 5 * the scale of 7. = 35
So there should be 35 black keys.
Using proportions, it is found that 35 black keys appear on a portable keyboard with 49 white keys.
This question is solved by proportions, applying a rule of three.The equivalent ratio given, from the picture, is that for 7 white keys, there are 5 black keys. Hence, how many black keys will be there when there are 49 white keys?The rule of three is:
7 white keys - 5 black keys
49 white keys - x black keys
Applying cross multiplication:
[tex]7x = 49 \times 5[/tex]
Simplifying both sides by 7:
[tex]x = 7 \times 5 = 35[/tex]
Hence, 35 black keys will appear.
A similar problem, also involving proportions, is given at https://brainly.com/question/24372153
u=(-4,10) and v=(5,3) what is 3v+u?
This is Right answer....
Determine if the sequence below is arithmetic or geometric and determine the common difference / ratio in simplest form.
20, 15, 10
Answer:
a. T² - T¹ = d ( A. P) -5
b. T²/T¹ = r (G. P) 3/4
Step-by-step explanation:
a. 15 - 20 = -5
b. 15/20 = 3/4
Answer:
This is an arithmetic sequence and the common difference is equal to -5.
) As an ice cube melts its surface area is decreasing at a rate of 6cm2/sec. Find the rate at which the length of each side is decreasing at the moment when each side has length 2 cm. [Hint: a cube has 6 sides and each side has area x 2 where x is the side length]
Answer:
The rate of decreasing of the length is 0.25 cm/s.
Step-by-step explanation:
The surface area of the ice cube is:
[tex]A_{ice}=6x^{2}[/tex]
Where x is the side of the cube.
Let's take the derivative of A with respect to "t" to get the rate of change.
[tex]\frac{dA_{ice}}{dt}=12x\frac{dx}{dt}[/tex]
We know that dA/dt = 6 cm²/s and x is 2 cm, so we just need to solve it for dx/dt which is the rate change of the length.
[tex]6=12(2)\frac{dx}{dt}[/tex]
[tex]\frac{dx}{dt}=\frac{1}{4}\: cm/s[/tex]
Therefore, the rate of decreasing of the length is 0.25 cm/s.
I hope it helps you!
A fruit salad recipe calls for 3/4 pound of apples and 2/5 pound of dates. What is the least common denominator of the fractions?
Group of answer choices
Answer:
20
Step-by-step explanation:
5 and 4 have no common factors until they are multiplied by each other. So if you were to convert your existing measurements, you would do the following.
(3/4) x (5/5)
(2/5) x (4/4)
Giving you 15/20 and 8/20
will give more points if correct
Answer:
REVENGE
Step-by-step explanation:
Similar Triangles
Write the ratio of corresponding sides for the similar triangles and reduce the ratio to lowest terms.
a. 14/27 = 21/28 = 14/27
b. 14/18 = 21/27 = 7/9
c. 14/21 = 18/27 = 2/3
d. 27/14 = 28/21 = 27/14
Please select the best answer from the choices provided
Answer:
B. 14/18 = 21/27 = 7/9
Step-by-step explanation:
I calculated it logically
A screening test for a disease shows a positive result in 91% of all cases when the disease is actually present and in 7% of all cases when it is not. Assume that the prevalence of the disease is 1 in 650. If the test is administered to a randomly chosen individual, what is the probability that the result is positive
Answer:
0.0713 = 7.13% probability that the result is positive.
Step-by-step explanation:
Probability of a positive test:
91% of 1/650(has the disease).
7% of 1 - 1/650 = 649/650(does not have the disease). So
[tex]p = 0.91\frac{1}{650} + 0.07\frac{649}{650} = \frac{0.91 + 0.07*649}{650} = 0.0713[/tex]
0.0713 = 7.13% probability that the result is positive.
WILL GIVE U BRAINLIEST
True or False: All obtuse triangles are scalene?
Answer:
False
Step-by-step explanation:
an obtuse triangle maybe isosceles or scalene
. In this exercise, you will conduct regression analysis with binary and categorical variables. (a) Use the command tabulate to show the categories of the variable occupation and their frequencies. What is the relative frequency of the category Sales
A rectangle measures 2
1
2
meters by 1
3
4
meters. What is its area?
Answer:
28408
Step-by-step explanation:
212x134=28408
Find the area of a regular polygon with 9 sides that has a side length of 12 inches and an apothem of 15 inches.
Answer:
An apothem is a line drawn from the centerpoint of the polygon to one side of the polygon. There is a formula for area in terms of apothem:
A = (1/2)*(Perimeter)*(Apothem)
The perimeter of the regular polygon is just the length of one side multiplied with the number of sides. Since a polygon with 9 sides,
P = 9(15) = 135in
A = 1/2 ×135 × 12
A = 810 square inches ans
Describe the relationship of the formula.
y = kx
If two variables (x and y) are directly proportional to each other, their relationship can be described as y=kx, where k is how they change relative to one another
The average domestic economy car gets around 30.9 miles per gallon (MPG) with a standard deviation of 2.88. Suppose domestic manufacturers all vow to increase fuel economy over the next 2 years. If successesful, 2.9 is added to every observation in the dataset. What is the new mean
Answer:
33.8
Step-by-step explanation:
Given that :
Initial Average miles per gallon = 30.9
Uniform value added to each data in the set = 2.9
The mean value of a dataset shifts by the uniform value added to each value in the dataset. This is always true whenever a uniform value is added to values across a dataset irrespective of the number of samples.
Hence
Initial mean. + uniform Value
30.9 + 2.9 = 33.8
Mike has a bank account whose balance is represented by A(t)=10,000*3.138^t. Where t is in years. Write the function so it reflects the monthly rate of interest . Around the nearest percent
9514 1404 393
Answer:
A(m) = 10000×1.10^m; 10% monthly interest
Step-by-step explanation:
If t is the time in years and m is the corresponding time in months, then we have ...
m = 12t
t = m/12
So, the balance is ...
A(t) = 10000×3.138^t
A(m) = 10000×3.138^(m/12) = 10000×(3.138^(1/12))^m
A(m) = 10000×1.10^m
The monthly interest rate is 10%.
_____
The monthly growth factor 1.10 is 1 more than the monthly growth rate.
growth rate = growth factor -1 = 1.10 -1 = 0.10 = 10%.
An observer in a blimp sights a football stadium at a certain angle of depression. If the blimp is at an altitude of 1600 ft and the horizontal distance between the blimp and stadium is 2372 ft. Determine the angle of depression from the blimp to the stadium to the nearest degree.
Answer:
http://maggieevans.weebly.com/uploads/8/3/6/6/8366984/unit_2_test_review_answers.pdf
Step-by-step explanation:
The link is there it might have some other answers scroll down on the page link. No this is not a scam i promise <3
Which inequality is represented by the graph below?
A jar has 1 white marble and 2 red marbles in it. If Jerry picks out 2 marbles without looking inside, what is the probability that he will pick two of the same color?
A. 1/3
B. 1/2
C. 2/3
D. 3/2
Answer:
C) 2/3
Step-by-step explanation:
The 2 represents the two Jerry picked out and the 3 represents the total amount of marbles.
Hope this helped :)
Answer:
A. 1/3
Step-by-step explanation:
Chance of red on one marble
2/3
Chance of red on second marble
1/2
Chance both red
2/3 * 1/2 = 1/3
Hi plz help, if you can ill mark you 5 starz! :)
Answer:
Part A = A
Part B - 308
A skateboard ramp rises 2 feet for every 7 feet measured horizontally. What is the slope?
Express the area of the entire rectangle.
Your answer should be a polynomial in standard form.
X+7
X+1
Area=
ASAP!!!!!!
Answer:
Area = x² + 8x + 7
Step-by-step explanation:
Area of a rectangle formula = L * W
Length (L) of the given figure = (x + 7)
Width (W) of the given figure = (x + 1)
Area = L * W
Area = (x + 7) * (x + 1)
=> x * x = x²
=> x * 1 = 1x or x
=> 7 * x = 7x
=> 7 * 1 = 7
Combining it all together;
Area = x² + 1x + 7x + 7
Combine the like terms:
Area = x² + 8x + 7
Hope this helps!
The area of the entire rectangle in the polynomial form will be x² + 8x + 7.
What is the area of the rectangle?Let W be the rectangle's width and L its length. The area of the rectangle is the multiplication of the two different sides of the rectangle. Then the rectangle's area will be given as,
Area of the rectangle = L × W square units
The dimensions of the big rectangle are x + 1 high and x + 7 long. Then the area of the rectangle is calculated as,
A = (x + 7)(x + 1)
Simplify the equation, then we have
A = (x + 7)(x + 1)
A = x² + 7x + x + 7
A = x² + 8x + 7
More about the area of the rectangle link is given below.
https://brainly.com/question/20693059
#SPJ2
Need help fast please thanks
Answer:
c = 41 ft
Step-by-step explanation:
To solve this problem, we can use the pythagorean theorem, which is defined by the formula [tex]a^2+b^2=c^2[/tex]. We are given both the lengths of the legs, so all we need to do is to plug them both in and solve for c:
[tex]9^2+40^2 = c^2\\c^2 = 81 + 1600\\c^2 = 1681\\c = 41[/tex]
This is the first option.
Numerical Response
15b - 6 - 3b + 10
This polynomial simplifies to the form
nb + m
then n + m=?
Answer:
[tex]\huge\boxed{Answer\hookleftarrow}[/tex]
[tex]15b - 6 - 3b + 10 \\ 15b - 3b - 6 + 10 \\ = 12b + 4[/tex]
12b + 4 is in the form nb + m, where,
n = 12m = 4So,
[tex] = n + m \\ = 12 + 4 \\ = 16[/tex]
✐ 16 is the correct answer.
ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ
# ꧁❣ RainbowSalt2²2² ࿐
. The volume of a box is 405 cubic units. The length is x units, the width 4 units greater than the length, and the height is 9 units. Find the length and width of the box.
Answer:
length = 5
width = 9
Step-by-step explanation:
V = lwh
let 'x' = length
let '4+x' = width
9 = height
405 = 9x(4+x)
405 = 36x + 9x²
this is a quadratic equation: 9x² + 36x - 405 = 0
factor out a 9 to get:
9(x² + 4x - 45) = 0
9(x-5)(x+9) = 0
one root is 5 and the other is -9
since distance cannot be negative we use 5 as the length and 9 is the width
~Help please and ty~ ✨Brainilist✨
Answer:
-37
Step-by-step explanation:
-37/100 is rational.
Answer:
-37/100
Step-by-step explanation:
Harvey is often late for work. He leaves home late 60% of the time, but then drives very fast. This gives him a 50% chance of getting to work on time. When Harvey leaves home on time, he drives so slowly that he is late 70% of the time. What is the probability that Harvey left home on time if he gets to work on time
Answer:
40%
Step-by-step explanation:
X - 13 < -11 Does anyone know this
Answer:
x < 2
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightEquality Properties
Multiplication Property of Equality Division Property of Equality Addition Property of Equality Subtraction Property of EqualityStep-by-step explanation:
Step 1: Define
Identify
x - 13 < -11
Step 2: Solve for x
[Addition Property of Equality] Add 13 to both sides: x < 2Here we see that any value x smaller than 2 would work as a solution.
Evaluate 3x + y if x = 1.5 and y = 1/2
Step-by-step explanation:
3x + y
3(1.5)+0.5
=5
!!!!!!!!!!
Answer:
5
Step-by-step explanation:
3x + y = ?
3 (1.5) + 1/2 = ?
4.5 First let's convert 4.5 into a fraction
4.5 = [tex]\frac{9}{2}[/tex] Then convert it has a mixed number
[tex]4\frac{1}{2}[/tex] + [tex]\frac{1}{2}[/tex] = 5
Last Question Plz Help
Answer:
this is good looking nice photo but li can't give you answer of that sorry.
Step-by-step e this https://www.commonlit.org/en/students/student_lesson_activities
Find the quotient of these complex numbers (6-I) divided by (4+3i)=
Answer:
[tex]\frac{21}{25} -\frac{22}{25} i[/tex]
Step-by-step explanation:
We can start by writing the division as a fraction:
[tex]\frac{6-i}{4+3i}[/tex]
In order to rationalize the denominator, we need to multiply by the conjugate:
[tex]\frac{6-i}{4+3i} *\frac{4-3i}{4-3i}\\\\\frac{(6-i)(4-3i)}{4^2-(3i)^2}\\\\\frac{24-18i-4i+3i^2}{16+9}\\\\\frac{24-22i-3}{25}\\\\\frac{21-22i}{25} \\\\\frac{21}{25} -\frac{22}{25} i[/tex]
This line is parallel to the line 2x + 6y = 12.
Answer:
y = 1/3x + 4 1/3
hope this helps
have a good day :)
Step-by-step explanation:
Answer:
[tex]6y = - 2x + 12 \\ 3y = - x + 6 \\ y = - \frac{1}{3} x + 2[/tex]