Class 7 Maths Sample Equations | Important Questions For Exam
IMPORTANT QUESTIONS FOR CBSE EXAMINATION | CLASS 7 MATHEMATICS
SIMPLE EQUATIONS – Chapter 4
Answer the following (2 marks):
1. Write the following statements in the form of equations.
a) 3 added to twice a number y is 25
b) If you subtract 4 from three times of a number x, you get 8.
2. Solve the following equations:
a) x + 5 = 15
b) 3 + 2z = 17
3. Manu’s father’s age is 3 years more than three times Manu’s age. If Manu’s father’s age is 36 years old, what will be Manu’s age?
4. Check whether the value given is a solution or not?
a) 4p- 2 = 10 (p = 3)
b) 5n + 5 = 10 (n=2)
5. Write the following in statement form:
a) 2x + 3 = 9
b) 4y – 2 = 10
6. Set up an equation and solve:
The age of mother is five times the age of her daughter and the sum of their ages is 42. Find the age of daughter?
7. Solve:
a)2p + 9 = 29
b) 10p + 10 = 100
8. Solve:
a) 3(x + 8) = 24
b) 2(2 – y) = 8
9. Set up an equation and solve:
a) When I subtracted 7 from thrice a number x, the result was 20.
b) Add 8 to 3 times a number y, you get 17.
10. a)Construct 2 equations starting with x = 3
b) Construct 2 equations starting with x = -3
ANSWERS:
1. a)3 + 2y = 25
b) 3x – 4 = 8
2. a) x + 5 = 15
x = 15 – 5 = 10
b) 3 + 2z = 17
2z = 17 – 3 = 14
z = 14/2 = 7
3. Let Manu’s age be x.
Then father’s age = 3 + 3x
Given 3 + 3x = 36
3x = 36 – 3 = 33
x = 33/3 = 11
4. a) 4p-2 = 10
When p = 3, 4p -2 = 4 x 3 – 2 = 12 – 2 = 10
So p=3 is a solution of the equation.
b) 5n + 5 = 10
When n = 2, 5n + 5 = 5 x 2 + 5 = 10 + 5 =15
So n = 2 is not a solution of the equation.
5. a) Three added to twice a number x is 9.
b) Two subtracted from four times a number y is 10.
6. a) Let daughter’s age be x.
Mother’s age = 5x
Given x + 5x = 42
6x = 42
x = 42/6 = 7
7. a) 2p + 9 = 29
2p = 29 – 9 = 20
P = 20/2 = 10
b) 10 p + 10 =100
10p = 100- 10 = 90
P = 90/10 = 9
8. a) 3(x + 8) = 24
x + 8 = 24/3 = 8
x = 8 – 8 = 0
b) 2 (2 – y) = 8.
2 – y = 8/2 = 4
-y = 4 – 2 = 2
Y = -2
9. a) 3x – 7 = 20
3x = 20 + 7 = 27
x = 27/3 = 9
b) 8 + 3y = 17
3y = 17 -8 = 9
Y = 9/3 = 3
10. a) 3x + 2 = 11
4x – 2 = 10
b) 5x + 7 = -8
3x = -9
