## Ncert Solutions for Class 6 Maths Chapter 11 Algebra Exercise 11.4:-

**Exercise 11.4**Ā Class 6 maths NCERT solutions Chapter 11 Algebra pdf download:-

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### Ncert Solution for Class 6 Maths Chapter 11 Algebra Exercise 11.4 Tips:-

**Using Expressions Practically**

We have already come across practical situations in which expressions are

useful. Let us remember some of them.

Situation (described inĀ Ā Variable Statements using

ordinary language) expressions

1. Sarita has 10 more Let Ameena Sarita has

marbles than Ameena. have x marbles. (x + 10) marbles.

2. Balu is 3 years Let Rajuās age Baluās age is

younger than Raju. be x years. (x ā 3) years.

3. Bikash is twice Let Rajuās age Bikashās age

as old as Raju. be x years. is 2x years.

4. Rajuās fatherās Let Rajuās age Rajuās father’s

age is 2 years more be x years. age is (3x + 2)

than 3 times Rajuās age. years.

**Let us look at some other such situations.**

Situation (described in Variable Statements using

ordinary language) expressions

5. How old will Susan Let y be Susanās Five years from

be 5 years from now? present age in years. now Susan will

be (y + 5) years old.

6. How old was Susan Let y be Susanās Four years ago,

4 years ago? present age in years. Susan was (y ā 4) years old.

7. Price of wheat per kg Let price of rice Price of wheat

is Rs 5 less per kg be Rs p. per kg is Rs (p ā 5).

than price of rice per kg.

8. Price of oil per litre Let price of rice Price of oil per

is 5 times the price of per kg be Rs p. litre is Rs 5p.

rice per kg.

9. The speed of a bus is Let the speed of the The speed of the

10 km/hour more than truck be y km/hour. bus is (y + 10) km/hour.

the speed of a truck

going on the same road.

Try to find more such situations. You will realise that there are many

statements in ordinary language, which you will be able to change to statements

using expressions with variables. In the next section, we shall see how we use

these statements using expressions for our purpose.

**What have we discussed?**

1. We looked at patterns of making letters and other shapes using matchsticks. We

learnt how to write the general relation between the number of matchsticks

required for repeating a given shape. The number of times a given shape is

repeated varies; it takes on values 1,2,3,… . It is a variable, denoted by some

letter like n.

2. A variable takes on different values, its value is not fixed. The length of a square can

have any value. It is a variable. But the number of angles of a triangle has a fixed value 3. It is not a variable.

3. We may use any letter n, l, m, p, x, y, z, etc. to

show a variable.

4. A variable allows us to express relations in any

practical situation.

5. Variables are numbers, although their value is not

fixed. We can do the operations of addition,

subtraction, multiplication and division on them

just as in the case of fixed numbers. Using

different operations we can form expressions

with variables like x ā 3,

x + 3, 2n, 5m, 3p, 2y + 3, 3l ā 5, etc.