Constant of Proportionality

Q.

The fourth proportional to $4,6,8$Is What.

Q.

Which equation has a constant of proportionality equal to 4?

1. xy=4

2. y=5x

3. 4x=4y

4. $y=\frac{1}{4}x$

Q. A picture is 60 cm wide and 1.8 m long. The ratio of its width to its perimeter in lowest form is

1. 1 : 2
2. 1 : 3
3. 1 : 4
4. 1 : 8

Q.

The radius of a circle is proportional to its diameter. Find the constant of proportionality.

Q.

A foot path of uniform width runs all around inside of a rectangular field 45m long and 36m wide. If the area of the path is 234m^2, find the width of the path

Q.

The area of an $A_0$ paper is one square metre. What are the lengths of the sides of an $A_3$ paper ? (answer in millimetres)

1. 296.32, 210

2. 296.4, 148.49

3. 480.382, 297.3

4. 420, 210

Q.

Which of the following equations has a constant of proportionality equal to 1?

1. $y=\frac{3}{5}x$

2. xy=2

3. y=x

4. x= 3y

Q. If mass is proportional to volume, then the constant of proportionality is .

1. mass
2. density
3. volume

Q.

Question 77 (i)

From the following table determine if x and y are in direct proportion.

1. x and y are in proportion.

2. x and y are not in proportion.

Q.

7 is the mean proportion between two numbers x and y and 56 is third proportion to x and y. Find the numbers.

1. x = 2.5, y = 16

2. x = 1.5, y = 12

3. x = 4, y = 14

4. x = 3.5, y = 14

Q.

Given that x and y are in inverse proportion, and $y_1$ $y_2$ are values of $y$ corresponding to the values $x_1$$x_2$ of $x$ respectively. Which of the following is correct?

1. x₁y₂=x₂y₁

2. x₁y₁=x₂y₂

3. x₁x₂=y₁y₂

4. =

Q.

What is the constant of proportionality in the relation of the area of an equilateral triangle to the square of length of its side?

1. $\frac{\sqrt{4}}{3}$
2. 1
3. $\frac{\sqrt{3}}{4}$
4. $\frac{4}{\sqrt{3}}$

Q.

Consider the equation $y=\sqrt{2}x$. Which of the following is/are true?

1. y is inversely proportional to x.

2. The constant of proportionality is $\sqrt{2}$

3. y is directly proportional to x.

4. y is directly proportional to square root of x.

Q.

Find $x$ in the given proportions: $10:x=80:32$.

Q. Area of a square is the square of its side length.

1. True
2. False

Q. Check which of the following is/are solution of the equation $x-2y=4$:

1. $\left(0,2\right)$
2. $\left(2,0\right)$
3. $\left(4,0\right)$
4. $\left(\sqrt{2},4\sqrt{2}\right)$

Q. If x = 24, y = 8 and x is proportional to y, then the constant of proportionality is:

1. 3
2. 6
3. 1
4. 2

Q.

Rahul is constructing a square of dimensions (5, 5). Rohan is constructing a rectangle of dimensions (6, 4). Then, which of the following statements hold true?

1. Area of Rohan's rectangle > Area of rahul's square

2. Area of Rohan's rectangle < Area of rahul's square

3. Area of Rohan's rectangle = Area of Rahul's square

4. Area of Rohan's rectangle is 20 square units. Area of Rahul's square is 30 square units.

Q.

What is the constant of proportionality in the equation for proportional change $y=\frac{k}{x}$ ?

1. k

2. $\frac{1}{k}$

3. 0

4. 1

Q. What is the constant of proportionality in the equation of change $y=kx$ ?

1. k
2. 1:k
3. $\frac{1}{k}$
4. k:1

Q.

The height of figure A is $9\mathrm{feet}$. The height of a familiar figure B is $15\mathrm{feet}$. What is the value of the ratio of the perimeter of A to the perimeter of B?

Q. If the area of a square is 100 units, find its area when the length of its side is doubled.

1. 600 sq units
2. 800 sq units
3. 900 sq units
4. 400 sq units

Q.

Let the speed of an object falling from a certain height be given by the equation $y=10x$, where $x$ indicates time. Which of the following is(are) true?

1. 10 is the constant of proportionality

2. As time increases , speed decreases

3. Speed and time are proportional.

4. Speed and time are not proportional.

Q.

Which of the following equations have a constant of proportionality equal to 2?

1. y = 2x

2. y = x+2

3. $yx=\frac{1}{2}$

4. y+2=2x

Q. A mother's age is 2 more than the square of the son's age and the sum of their ages is 44. Find the son's age.

1. 7
2. 6
3. 5
4. 4

Q. If y is directly proportional to x & when $x=2$ & $y=4$, what is constant of proportionality?

1. $1$
2. $3$
3. $5$
4. $2$

Q. If 9, x, x and 49 are in proportion, find the value of x.

1. 7
2. 14
3. 21
4. 35

Q.

Which of the following ratios , form a proportion ?

1. $2:5$and $5:7$

2. $4:11$ and $11:4$

3. $5:6$ and $25:30$

4. $7:13$ and $9:16$

Q.

What is the constant of proportionality in the equation of change of area with respect to the square of the length of a side?

1. 1

2. 1/4

3. 2

4. 4

Q.

Which is the odd one out?

1. 

2. 

3. 

4.