8th Standard CBSE Syllabus & Materials
8th Standard CBSE
CBSE 8th Social Science Theme D - Factors of Production - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme C - Universal Franchise and India's Electoral System - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme B - The Rise of the Marathas - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme B - Reshaping India's Political Map - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme A - Natural Resources and Their Use - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Science Keeping Time with Skies - New Model Questions Papers Study Material - QB365 Set A

Published on: 31/07/2018
From the chapter Linear Equations in One Variable, some of the important questions are covered in this question paper.
Teachers can prepared question paper with answer key within five minutes. Please Click Here for subscribe.
Download CBSE Class 8th Standard CBSE Mathematics question papers, sample papers, important questions, and previous year solved papers in PDF format. Get free study materials, NCERT solutions, and exam preparation resources for Class 8th Standard CBSE Mathematics
Questions + Answers key
Take MCQ Mathematics Test

1.
Find the Solution of \(\frac { 3m-5 }{ m-3 } (4m-6)=2m-3\)
2.
\(\frac { 1 }{ x+1 } +\frac { 1 }{ x+2 } =\frac { 2 }{ x+10 } \)
3.
Sum of two numbers is 95. If one exceeds the other number by 37. Find the numbers.
4.
Solve the following equations \(\frac { x }{ 3 } +1=\frac { 7 }{ 15 } \)
5.
Find the Solution of \(\frac { 5 }{ 4 } -7y=\frac { -23 }{ 4 } \)
6.
Two different equations can never have the same answer.
7.
In a two-digit number, the unit's place digit is x. If the sum of digits be 9, then the number is (10x - 9).
8.
If 16x = 80, then 18x = 90
9.
RHS means the expression on the right of the equality sign and LHS means the expression on the left of the equality sign.
10.
\(\frac { 7p }{ 3 } +6=1\) When +6 is transposed to RHS, then it \(\frac { 7p }{ 3 } =\frac { 1 }{ 6 } \)
11.
Anushka and Aarushi are friends. They have equal amount of money in their pockets. Anushka gave of her money to Aarushi as her birthday gift. Then, Aarushi gave a party at a restaurant and cleared the bill by paying half of the total money with her. If the remaining money in Aarushi's pocket is Rs.1600, then find the money gifted by Anushka.
12.
Find the root of the equation \(\frac { \left( 2+y \right) \left( 7-y \right) }{ \left( 5-y \right) \left( 4+y \right) } =1\)
13.
Simplify and solve the following linear equation 3(5y - 7) - 2 (9y - 11) = 4 (8y - 13) - 17 Also check you answer
14.
Solve \(\frac { 17-3x }{ 5 } -\frac { 4x+2 }{ 3 } =5-6x+\frac { 7x+14 }{ 3 } \)
15.
The ages of Rahul and Hamon are in the ratio 5 : 7. Four years later, the sum of their ages will be 56 yr. What are their present ages?
16.
Arpita's present age is thrice of Shilpa. If Shilpa's age 3 yr ago was x. Then, Arpita's present age is
3(x - 3)
3x + 3
3x - 9
3(x + 3)
17.
A linear equation in one variable has
only one solution
no solution
two solutions
more than two solutions
18.
If a and b are positive integers, then solution of the equation ax = b has to be always
positive
negative
One
Zero
19.
Linear equation in one variable has
only one variable with any power
only one term with a variable
only one variable with power 1
only constant term
20.
The Solution of the equation ax+b = 0 is
\(x=\frac { a }{ b } \)
x = -b
\(x=\frac { -b }{ a } \)
\(x=\frac { b }{ a } \)
21.
If 4t - 3 - (3t + 1)= 5t - 4, then the root of t is.....
22.
After 18 yr, Saurabh will be 4 times as old as he is now. His present age is...........
23.
If on dividing a number by 18, the result is -144, then the number is.................
24.
Any value of the variable, which makes both sides of an equation equal is known as a .......... of the equation.
25.
In a linear equation, ............power of the variable appearing in the equation is one.
26.
Sahil and Suraj are close friends. Sahil's monthly salary is 3 times less than Suraj. Suaj helps Sahil every month with Rs.6000, after which Sahil is left with total money half of the money Suraj has. Then,
(a) find the salary of Sahil and Suraj.
(b) what type of value is depicted by Suraj
27.
Abdul buys two kinds of cloth material for school uniforms, shirt material which costs him Rs. 50 per metre and trouser material that costs him Rs. 90 per metre. For every 2 m of the trouser material, he buys 3 m of the shirt material. He sells the material at 12% and 20% profit, respectively. His total sale is Rs. 38160. How much trouser material did he buy?
1.
Given \(\frac { 3m-5 }{ m-3 } (4m-6)=2m-3\)
\(\Rightarrow\) \(\frac { 3m-5 }{ m-3 } +2m-3=2m-3\quad \Rightarrow \frac { 3m-5 }{ m-3 } =0\)
\(\Rightarrow\) \(3m-5 = Ox(m-3)\) \(\Rightarrow\) 3m - 5 =0
3m = 5 m= \(\frac { 5 }{ 3 } \)
2.
\(x=\frac { -26 }{ 17 } \)
3.
29 and 66
4.
\(x=\frac { -8 }{ 5 } \)
5.
We have, \(\frac { 5 }{ 4 } -7y=\frac { -23 }{ 4 } \Rightarrow -7y=\frac { -23 }{ 4 } -\frac { 5 }{ 4 } \) [ transpoting \(\frac { +5 }{ 4 } \) to RHS]
\(-7y=\frac { -28 }{ 4 } \) \(\Rightarrow -7y=-7\) [\(\because \) - 7y = (-7)x y]
y = -7 \(\div \) (-7) [transpoting x (-7) to RHS]
y = -7 x \(\left( -\frac { 1 }{ 7 } \right) \) \(\Rightarrow \) y =1
So, Y=1 is the solution of the given liner Equation
6.
(b)
7.
(b)
8.
(a)
9.
(a)
10.
(b)
11.
Suppose, Anushka and Aarushi have their equal amount of sum, which is Rs. x
After giving \(\frac { 1 }{ 3 } \) of the money to Aarushi,
Anushka has the amount =Rs. \(\left( x-\frac { x }{ 3 } \right) \)
and then amount of Aarushi = Rs. \(\left( x+\frac { x }{ 3 } \right) \)
Now, as per the given condition, we have
\(\left( x+\frac { x }{ 3 } \right) -\frac { 1 }{ 2 } x\left( x+\frac { x }{ 3 } \right) =1600\)
\(\Rightarrow\) \(\left( x+\frac { x }{ 3 } \right) \left( 1+\frac { 1 }{ 2 } \right) =1600\)
\(\Rightarrow\)\(\left( x+\frac { x }{ 3 } \right) \times \frac { 1 }{ 2 } =1600\)
\(\Rightarrow\) \(\frac { 3x+x }{ 3 } =1600x2=3200\)
\(\Rightarrow\) \(\frac { 4x }{ 3 } =3200\Rightarrow x=3200x\frac { 3 }{ 4 } =2400\)
So, money gifted by Anushka = \(\frac { 1 }{ 3 } \)of 2400
\(\frac { 1 }{ 3 } \times 2400\) = Rs = 800
12.
we have \(\frac { \left( 2+y \right) \left( 7-y \right) }{ \left( 5-y \right) \left( 4+y \right) } =1\)
By cross-multiplication, we get
(2 + y)(7 - y) =(5 - y)(4 + y)
\(\Rightarrow\) 14 - 2y + 7y - y2 = 20 + 5y - 4y - y2
\(\Rightarrow\) 14 + 5y = 20 + Y \(\Rightarrow\) 5y - y = 20-14
\(\Rightarrow\) 4y = 6 \(\Rightarrow\) y = \(\frac { 6 }{ 4 } =\frac { 3 }{ 2 } \)
Thus, solution of the given equation is \(\frac { 3 }{ 2 } \)
13.
We have, 3(5y - 7) - 2(9y - 11) = 4(8y - 13) - 17
15y - 21-18y + 22 = 32y - 52 -17
\(\Rightarrow\) -3y + 1 = 32y-69
1+ 69 = 32y + 3y \(\Rightarrow\) 70 = 35y \(\Rightarrow\) Y = 2
On putting y = 2 in both sides of the given equation, we get
3(5 x 2 - 7) - 2(9 x 2 -11) = 4(8 x 2 -13)-17
\(\Rightarrow\) 3(10 -7) - 2(18 -11) = 4(16 -13) -17
\(\Rightarrow\) 3 x 3 - 2 x 7= 4 x 3 - 17
\(\Rightarrow\) 9-14 = 12 - 17 - 5 = -5
LHS = RHS
So, y = 2 is solution of the given linear equation
14.
We have\(\frac { 17-3x }{ 5 } -\frac { 4x+2 }{ 3 } =5-6x+\frac { 7x+14 }{ 3 } \)
Multiplying both sides by 15 i.e. the LCM of 5 and 3, we get
3 (17 - 3x) - 5 (4x + 2) = 15 (5 - 6x) + 5 (7x + 14)
\(\Rightarrow\) 51- 9x - 20x - 10 = 75 - 90x + 35x + 70 \(\Rightarrow\) 41- 29x = 145 - 55x [transposing -55x to RHS and 41 to LHS
\(\Rightarrow\) -29x + 55x = 145 - 4
\(\Rightarrow\) 26x = 104 \(\Rightarrow\) \(\frac { 26x }{ 26 } =\frac { 104 }{ 26 } \) \(\Rightarrow\) x = 4 [dividing both sides by 26]
Hence, x = 4 is the solution of the given equation
15.
Let the present ages of Rahul and Haroon be 5x yr and 7x yr, respectively.
4 yr later, age of Rahul = (5x + 4)yr
and age of Haroon=(7x + 4)yr
According to the question,
(5x + 4) + (7x + 4) = 56
\(\Rightarrow\) 5x + 4 + 7x + 4 = 56 \(\Rightarrow\) 12x = 56 - 8
\(\Rightarrow\) 12x = 56 -8 [transposing 8 to RHS]
\(\Rightarrow\) 12x = 48 \(\Rightarrow\) x=\(\frac { 48 }{ 12 } \)=4 [dividing both sides by 12]
\(\therefore\) Present age of Rahul = 5x = 5 x 4 = 20 yr
and present age of Haroon = 7x = 7 x 4 = 28 yr
Hence, their present ages are 20 yr and 28 yr.
16.
(d)
3(x + 3)
17.
(a)
only one solution
18.
(a)
positive
19.
(c)
only one variable with power 1
20.
(c)
\(x=\frac { -b }{ a } \)
21.
( )
4t - 3 - (3t + 1)= 5t - 4
\(\Rightarrow\) 4t - 3 - 3t - 1= 5t - 4 \(\Rightarrow\) t - 4 = 5t - 4
\(\Rightarrow\) t - 5t =-4 +4 -4t = 0 \(\Rightarrow\) t = 0
22.
( )
\(\because\) x + 18 = 4x \(\Rightarrow\) 4x - x = 18
3x = 18 \(\Rightarrow\) x = 6yr
23.
( )
\(\because \frac { -2592 }{ 18 } =-144\)
24.
( )
Solution
25.
( )
Highest
26.
Let Sahil's monthly salary be Rs. x
Then, Suraj's monthly salary = Rs. 3x
After giving Rs. 6000 to Sahil, Sahil has money
= x + 6000 and Suraj has money = 3x - 6000
Then, according to the question,
2(x + 6000) = (3x -6000)
\(\Rightarrow\) 2x + 12000 = 3x - 6000
\(\Rightarrow\) 3x - 2x =12000+ 6000 =18000
x =18000
So, Sahil's monthly salary = Rs.18000
and Suraj's monthly salary = Rs. 54000.
(b) The value depicted by Suraj is their helpful nature. He helps his friend in the need
27.
Let Abdul buys 2x m of trouser material
Then, the shirt material bought by him = 3x m
Sale price of 1 m of trouser material
Rs (90 + 12% of 90)
\(\left( 90+\frac { 12\times 90 }{ 100 } \right) =Rs.100.80\)
Sale price of 2x m of trouser material = Rs.(2xx 100.80) = Rs. 201.60x
Sale price of 1m of shirt material
Rs. 50 +20% of Rs 50 = \(\left( 50+\frac { 20\times 50 }{ 100 } \right) =Rs.60\)
Sale price of 3x m of shirt material = Rs 3x x 60
= Rs. 180x
Total sale = Rs. (201.60+180) x = Rs. 381.60x
\(\therefore\) 381.60 = 38160
\(x=\frac { 38160 }{ 38.160 } =100\)
So,Abdul bought 2 x 100 = 200 m of trouser material.
8th Standard CBSE Syllabus & Materials
8th Standard CBSE
CBSE 8th Science Particulate Nature of Matter - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Science Pressure, Winds, Stroms and Cyclones - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Mathematics Quadrilaterals - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Mathematics A story of Numbers - New Model Questions Papers Study Material - QB365 Set A
CBSE 8th Standard CBSE Subjects
CBSE Standards