# Important Questions for CBSE Class 6 Maths Chapter 11 - Algebra

## CBSE Class 6 Maths Important Questions Chapter 11 - Algebra - Free PDF Download

**Ch-11 ****Algebra**

- Radha is drawing a dot Rangoli (a beautiful pattern of lines joining dots with chalk powder. She has 10 dots in a row. How many dots will her Rangoli have for r rows?
- 10 + r
- 10r
- 10 – r
- r

- Which of the following is expression with one variable?
- x + y + z
- y + 1
- 1
- x + y – 5

- The length of a rectangular hall is 4 meters less than 3 times the breadth of the hall. What is the length, if the breadth is b meters?
- 12b
- 3b – 4
- None of these
- 3b + 4

- The _______ of the variable in an equation which satisfies the equation is called a solution to the equation.
- value
- factor
- term
- None of these

- The teacher distributes 4 pencils per student. Can you tell how many pencils are needed for given number of students? (Use s for the number of students.)
- 4 – s
- 4+s
- s
- 4s

**Match the following:**Column A Column B (a) 3 times y added to 13 (p) 5y – 8 (b) 8 subtracted from 5 times y (q) 3x – 5 (c) 5 reduced from 3 times x (r) 2x + 5 (d) 5 added to double of x (s) 3y + 13 **Fill in the blanks:**- The value of 2x – 12 is zero, when x = ________.
- The product of 2 and x is being added to the product of 3 and y is expressed as ________.
- The numerical coefficient of the terms $\frac{1}{2}x{y}^{2}$ is _________.
- The no. of terms in the expression $3{x}^{2}y\u20134{x}^{2}{y}^{2}+\frac{1}{2}x{y}^{2}\u20135x$ is ______.

**State whether the following statements are true or false:**- The parts of an algebraic exponent which are connected by + or – sign are called its terms.
- 5 times x subtracted from 8 times y is 5x-8y.
- A number having fixed value is called variable.
- The numerical coefficient of -2x
^{2}y is -2.

Write which letters give us the same rule as that given by L.

Rearrange the terms of the following expressions in ascending order of powers of x:

5x^{2}, 2x, 4x^{4}, 3x^{3}, 7x^{5}Give expressions for the following

- 7 added to
- 7 subtracted from
- p multiplied by
- p divided by
- 7 subtracted
- – p multiplied by
- – p divided by
- p multiplied by – 5.

The teacher distributes 5 pencils per student. Can you tell how many pencils are needed, given the number of students ? (Use s for number of students.)

Form expressions using y, 2 and 7. Every expression must have y in it. use only two number operations. These should be different.

Find the value of the expression 2x – 3y + 4z, if x = 10, y = -12 and z = 11.

Deepak’s present age is one-third his mother’s present age. If the mother’s age was five times his age 6 years ago, what are their present ages?

**Answer**

- 10r, Explanation: Let the total number of rows be ‘r’.

As, No. Of dots in a row =10.

So, the dots needed for 10 rows = r x 10= 10r.

- 10r, Explanation: Let the total number of rows be ‘r’.
- y + 1, Explanation: The equation has one variable as “y” whose value is not known. therefore, the equation is in one variable.

- 3b – 4, Explanation: breadth of a rectangular hall = b meters

let length of a rectangular hall be ‘l’ meter

according to the question, l = 3 times the breadth – 4 = 3b – 4

- 3b – 4, Explanation: breadth of a rectangular hall = b meters
- value, Explanation: It is correct because the value of the variable must satisfy the equation.

- (d) 4s, Explanation: Let the number of pencils be ‘s’.

As, the number of pemcils distributed to each student= 4

Thus, No. of pencils for ‘s’ students = 4 x s= 4s.

- (d) 4s, Explanation: Let the number of pencils be ‘s’.
- $\to $ (s)
- $\to $ (p)
- $\to $ (q)
- $\to $ (r)

- 6;
- 2x + 3y;
- $\frac{1}{2}$;
- 4

- True
- False
- False
- True

- The other letters which give us the same rule as L are T, V and X because the number of matchsticks required to make each of them is 2.
- If the given terms are arranged in the ascending order of powers of x, we get,2x, 5x
^{2}, 3x^{3}, 4x^{4}, 7x^{5}. - p + 7
- p – 7
- 7p
- $\frac{p}{7}$
- – m – 7
- -5p
- $-\frac{p}{5}$
- – 5p.

- Number of pencils to be distributed to each student= 5And, let the number of students in class be ‘s’.
As per the logic, Number of pencils needed =(Number of students in the class) x. (Number of pencils to be distributed to one student )

So, Number of pencils needed= 5 x s =5s.

- The different expressions that can formed are: 2y + 7, 2y – 7, 7y + 2, 7y-2, (y/2) – 7, (y/7)-2, y – (7/2), y + (7/2)
- Given expression = 2x – 3y + 4z

If x = 10, y = -12 and z = 11,

The expression becomes, $(2\times 10)\u2013(3\times \u201312)+(4\times 11)$

= 20 – (-36) + 44

= 20 + 36 + 44

= 100. - Let present age of mother = x years

Deepak’s present age $=\frac{x}{3}years$

6 years ago, mother’s age = (x – 6) years

Deepak’s age $=\left(\frac{x}{3}\u20136\right)$ years

According to the problem, 6 years ago, mother’s age is 5 times Deepak age.

i.e., (x – 6) $=5\times \left(\frac{x}{3}\u20136\right)$

$x\u2013\frac{5x}{3}=\u201330+6$

$\frac{3x\u20135x}{3}=\u201324$

$\frac{\u20132x}{3}=\u201324$

$2x=24\times 3$

$x=\frac{72}{2}=36$

Therefore, present age of mother = 36 years and

Present age of Deepak $=\frac{x}{3}=\frac{36}{3}=12$years.