Mathematics

Linear Equations in One Variable

Question:

When 9 is subtracted from the product of p and 4, the result is 11. The value of p is—-.

Answer:

ncert-exemplar-problems-class-8-mathematics-linear-equations-in-one-variable-10

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Linear Equations in One Variable

Q 1.

When 9 is subtracted from the product of p and 4, the result is 11. The value of p is—-.

Q 3.

If numerator is 2 less than denominator of a rational number and when 1 is subtracted from numerator and denominator both, the rational number in its simplest form is 1/2. What is the rational number?

Q 4.

The share of A when Rs 25 are divided between A and B, so that A gets Rs 8 more than B, is——–.

Q 5.

4 (3p + 2) – 5 (6p – 1) = 2 (p – 8) – 6 (7p – 4)

Q 6.

The sum of four consecutive integers is 266. What are the integers?

Q 7.

In a two-digit number, digit in unit’s place is twice the digit in ten’s place. If 27 is added to it, digits are reversed. Find the number.

Q 8.

If –frac { 4 }{ 3 } y = –frac { 3 }{ 4 } then y is equal to
(a)-{ left[ frac { 3 }{ 4 } 
ight] }^{ 2 } (b)-{ left[ frac { 4 }{ 3 } 
ight] }^{ 2 }
(c){ left[ frac { 3 }{ 4 } 
ight] }^{ 2 } (d){ left[ frac { 4 }{ 3 } 
ight] }^{ 2 }

Q 9.

If  frac { 2 }{ 5 } x-2=5- frac { 3 }{ 5 } x,then x=——-.

Q 10.

There are 40 passengers in a bus, some with Rs 3 tickets and remaining with Rs 10 tickets. The total collection from these passengers is Rs 295. Find how many passengers have tickets worth Rs 3?

Q 11.

When a number is divided by 8, the result is -3. The number is——–.

Q 12.

3 years ago, the age of boy was y years. His age 2 years ago was (y — 2) years.

Q 13.

The age of A is five years more than that of B. 5 years ago, the ratio of their ages was 3 :2. Find their present ages.

Q 14.

ncert-exemplar-problems-class-8-mathematics-linear-equations-in-one-variable-1

Q 15.

frac { 0.2x+5 }{ 3.5x-3 } =frac { 2 }{ 5 }

Q 16.

8x-7-3x=6x-2x-3

Q 17.

Two equal sides of a triangle are each 4 m less than three times the third side. Find the dimensions of the triangle, if its perimeter is 55 m.

Q 18.

The value of x, for which the expressions 3x – 4 and 2x + 1 become equal, is
(a) -3 (b) 0
(c) 5 x (d) 1

Q 19.

If a and b are positive integers, then the solution of the equation ax = b has to be always
(a) positive (b) negative (c) one (d) zero

Q 20.

The number of boys and girls in a class are in the ratio 5 : 4. If the number of boys is 9 more than the number of girls, then number of boys is 9.

Q 21.

If x is an even number, then the next even number is 2(x +1).

Q 22.

Sum of the digits of a two-digit number is 11. The given number is less than the number obtained by interchanging the digits by 9. Find the number.

Q 23.

frac { 5(1-x)+3(1+x) }{ 1-2x } =8

Q 24.

After 12 years, Kanwar shall be 3 times as old as he was 4 years ago. Find his present age.

Q 25.

For what value of x is the perimeter of shape 186 cm?
ncert-exemplar-problems-class-8-mathematics-linear-equations-in-one-variable-42

Q 26.

The solution of the equation 2y = 5y-frac { 18 }{ 5 } is————.

Q 27.

After 18 years, Swarnim will be 4 times as old as he is now. His present age is——–.

Q 28.

In a 2-digit number, the unit’s place digit is x. If the sum of digits be 9, then the number is (10x – 9).

Q 29.

Sum of the ages of Anju and her mother is 65 years. If Anju’s present age is y years, then her mother’s age before 5 years is (60 – y) years.

Q 30.

If the sum of two consecutive numbers is 93 and one of them is x, then the other number is 93 – x.

Q 31.

Two numbers differ by 40. When each number is increased by 8, the bigger becomes thrice the lesser number. If one number is x, then the other number is (40 – x).

Q 32.

frac { 8}{ x } =frac { 5 }{ x-1 }

Q 33.

5(x-1)-2(x+8)=0

Q 34.

frac { x+1 }{ 4 } =frac { x-2 }{ 3 }

Q 35.

 frac { 2y-3 }{ 4 } -frac { 3y-5 }{ 2 } =y+frac { 3 }{ 4 }

Q 36.

The sum of three consecutive numbers is 156. Find the number which is a multiple of 13 out of these numbers.

Q 37.

The perimeter of a rectangle is 240 cm. If its length is increased by 10% and its breadth is decreased by 20%, then we get the same perimeter. Find the length and breadth of the rectangle.

Q 38.

For what value of x is the perimeter of shape 77 cm?

ncert-exemplar-problems-class-8-mathematics-linear-equations-in-one-variable-40

Q 39.

Which of the following is a linear expression?
(a) { x }^{ 2 } +1 (b) y + { y }^{ 2 }
(c) 4 (d) 1 + z

Q 40.

The value of S in frac { 1 }{ 3 } + S = frac { 2 }{ 5 } is
(a)frac { 4 }{ 5 } (b)frac { 1 }{ 15 }
(c)10 (d)0

Q 41.

9x – ……………….. = – 21 has the solution (- 2).

Q 42.

Shikha’s present age is p years. Reemu’s present age is 4 times the present age of Shikha. After 5 years, Reemu’s age will be 15p years.

Q 43.

If frac { x }{ 11 } , then x=frac { 11 }{ 15 } .

Q 44.

frac { 5x }{ 2x-1 } =2

Q 45.

frac { x }{ 5 } =frac { x-1 }{ 6 }

Q 46.

frac { x }{ 2 } -frac { 1 }{ 4 } left( x-frac { 1 }{ 3 } 
ight) =frac { 1 }{ 6 } left( x+1 
ight) +frac { 1 }{ 12 }

Q 47.

The volume of water in a tank is twice of that in the other. If we draw out 25 litres from the first and add it to the other, the volumes of the water in each tank will be the same. Find the volumes of water in each tank.

Q 48.

Anima left one-half of her property to her daughter, one-third to her son and donated the rest to an educational institute. If the donation was worth Rs 100000, how much money did Anima have?

Q 49.

If 1/2 is subtracted from a number and the difference is multiplied by 4, the result is 5. What is the number?

Q 50.

Hamid has three boxes of different fruits. Box A weighs 2frac { 1 }{ 2 } kg more than box B and Box C weighs 10frac { 1 }{ 4 }kg more than box B. The total weight of the three boxes is 48frac { 3 }{ 4 } kg. How many kilograms does box A weigh?