My Cart
Your Cart 0

    Your cart is empty.

  • Total (Amount) ₹0.00
NCERT Exemplar · Class 7 · Maths

Chapter 4: Simple Equations

Practice each question, then open the answer or worked solution.

Questions

55 questions
Q1Written answer

The solution of the equation ax + b = 0 is

(a) a/b (b) –b (c) –b/a (d) b/a

Show solutionHide solution
Worked solution

Solution:-

(c) –b/a

Consider the given equation ax + b = 0

Transpose ‘b’ to right hand side then it becomes –b.

ax = -b

x = -b/a

Q2Written answer

If a and b are positive integers, then the solution of the equation ax = b will always be a

(a) positive number (b) negative number (c) 1 (d) 0

Show solutionHide solution
Worked solution

Solution:-

(a) positive number

The solution of the given equation ax = b

x = b/a

Q3Multiple choice

Which of the following is not allowed in a given equation?

Show solutionHide solution
Worked solution

Solution:-

(d) Dividing both sides of the equation by the same number.

Q4Written answer

The solution of which of the following equations is neither a fraction nor an integer? (a) 2x + 6 = 0 (b) 3x – 5 = 0

(c) 5x – 8 = x + 4 (d) 4x + 7 = x + 2

Show solutionHide solution
Worked solution

Solution:-

(d) 4x + 7 = x + 2

Consider the equation 4x + 7 = x + 2

Transpose 7 to right hand side then it becomes –7 and x to Left hand side then it becomes – x.

4x – x = 2 – 7

3x = -5

x = -5/3

Q5Written answer

The equation which cannot be solved in integers is

(a) 5y – 3 = – 18 (b) 3x – 9 = 0

(c) 3z + 8 = 3 + z (d) 9y + 8 = 4y – 7

Show solutionHide solution
Worked solution

Solution:-

(c) 3z + 8 = 3 + z

Consider the equation 3z + 8 = 3 + z

Transpose 8 to right hand side then it becomes –8 and z to Left hand side then it becomes – z.

3z – z = 3 – 8

2z = -5

z = -5/2

Q6Written answer

If 7x + 4 = 25, then x is equal to

(a) 29/7 (b) 100/7 (c) 2 (d) 3

Show solutionHide solution
Worked solution

Solution:-

(d) 3

Consider the given equation 7x + 4 = 25

Transpose 4 to right hand side then it becomes –4

7x = 25 – 4

7x = 21

x = 21/7

x = 3

Q7Written answer

The solution of the equation 3x + 7 = – 20 is

(a) 17/7 (b) -9 (c) 9 (d) 13/3

Show solutionHide solution
Worked solution

Solution:-

(b) -9

Consider the given equation 3x + 7 = – 20

Transpose 7 to right hand side then it becomes –7

3x = -20 – 7

3x = -27

x = -27/3

x = -9

Q8Written answer

The value of y for which the expressions (y – 15) and (2y + 1) become equal is

(a) 0 (b) 16 (c) 8 (d) – 16

Show solutionHide solution
Worked solution

Solution:-

(d) – 16

Consider the given equation (y – 15) = (2y + 1)

Transpose -15 to right hand side then it becomes 15 and 2y to Left hand side then it becomes – 2y.

y – 2y = 15 + 1

-y = 16

y = -16

Q9Written answer

If k + 7 = 16, then the value of 8k – 72 is

(a) 0 (b) 1 (c) 112 (d) 56

Show solutionHide solution
Worked solution

Solution:-

(a) 0

Consider the given equation k + 7 = 16

To find out the value of K.

Transpose 7 to right hand side then it becomes -7

k = 16 – 7

k = 9

Then, the value of 8k – 72 will be,

= (8 × 9) – 72

= 72 – 72

= 0

Q10Written answer

If 43m = 0.086, then the value of m is

(a) 0.002 (b) 0.02 (c) 0.2 (d) 2

Show solutionHide solution
Worked solution

Solution:-

(a) 0.002

Consider the given equation 43m = 0.086

To find out the value of m.

m = 0.086/43

m = 0.002