Ncert Solutions For Class 6 Maths Chapter 11 Algebra Ex 11.5 Ncert Solutions For Class 6 Maths Chapter 11 Algebra Exercise 11.5 Class 6 Maths Chapter 11 Algebra Exercise 11.5 Class 6 Chapter 11 Exercise 11.5

## NCERT Solutions for Class 6 Maths Chapter 11 Algebra Ex 11.5

Question 1.**
**State which of the following are equations (with a variable). Give reason for your answer. Identify the variable from the equations with a variable.

**(a)**17 = x + 7

**(b)**(t-7)> 5

**(c)**42 =2

**(d)**(7 x 3)-19 = 8

**(e)**5 x 4 – 8 =2x

**(f)**x – 2 =0

**(g)**2m<30

**(h)**2n+1=11

**(i)**7=(11 x 5) -(12x 4)

**(j)**7=(11×2)+p

**(k)**20=5y

**(l)**latex]\frac { 3q }{ 2 } [/latex]<5

**(m)**z+12>24

**(n)**20-(10-5)=3×5

**(o)**7-x =5

Solution.

Question 2.

Complete the entries in the third column of the table.

Solution.

**(a)**Yes

**(b)**Yes

**(c)**No

**(d)**No

**(e)**No

**(f)**Yes

**(g)**No

**(h)**No

**(i)**Yes

**(j)**Yes

**(k)**No

**(l)**No

**(m)**No

**(n)**No

**(o)**No

**(p)**No

**(q)**Yes

Question 3.

Pick out the solution from the values given bracket next to each equation. Show that the values do not satisfy the equation.

**(a)** 5m – 60 (10, 5, 12, 15)

**(b)** n + 12 = 20 (12, 8, 20, 0)

**(c)** p-5 = 5 (0, 10, 5,-5)

**(d)** q2 = 7 (7, 2, 10, 14)

**(e)** r-4- 0 (4, – 4. 8, 0)

**(f)** x + 4 – . y (-2, 0, 2. 4)

Solution.

**(a)** **Solution is 12**

**For m = 10**

L.H.S. = 5 x 10 = 50 which is not equal to R.H.S.

**For m = 5**

L.H.S. = 5 x 5 = 25 which is not equal to R.H.S.

**For m = 15**

L.H.S. = 5 x 15 = 75 which is not equal to R.H.S.

(b) Solution is 8

For n = 12

L.H.S. = 12+12

= 24 which is not equal to R.H.S.

**For n = 20**

L.H.S. = 20+12

= 32 which is not equal to R.H.S.

**For n =0**

L.H.S. = 0+12

= 12 which is not equal to R.H.S.

**(c) Solution is 10**

**For p = 0**

L.H.S. = 0 – 5 = – 5 which is not equal to R.H.S.

**For p = 5**

L.H.S. = 5-5 = 0 which is not equal to R.H.S.

**For p = – 5**

L.H.S. = – 5 – 5 = – 10 which is not equal to R.H.S.

**(d) Solution is 14**

**For g = 7**

L.H.S. = q2 which is not equal to R.H.S.

**For q = 2**

L.H.S. = 22 = 1 which is not equal to R.H.S.

**For q = 10**

L.H.S. = 102 = 5 which is not equal to R.H.S.

**(e) Solution is 4**

**For r = – 4**

L.H.S. = -4-4

= – 8 which is not equal to R.H.S.

**For r = 8**

L.H.S. = 8-4 = 4 which is not equal to R.H.S.

**For r = 0**

L.H.S. = 0 – 4 = – 4 which is not equal to R.H.S.

**(f) Solution is – 2**

**For x = 0**

L.H.S. = 0 + 4 = 4 which is not equal to R.H.S. For x = 2

L.H.S. = 2 + 4 = 6 which is not equal to R.H.S.

**For x : = 4**

L.H.S. = 4 + 4 = 8 which is not equal to R.H.S.

Question 4.

**(a)** Complete the table and by inspection of the table find the solution to the equation m + 10 = 16

**(b)** Complete the table and by inspection of the table find the solution to the equation 5t = 35

**(c)** Complete the table and find using the table the solution of the equation z/3 = 4

**(d)** Complete the table and find the solution to the equation m-7=3

Solution.

Question 5.

Solve the following riddles, you may yourself construct such riddles.

**Who am I?
(i)** Go round a square

Counting every corner

Thrice and no more!

Add the count to me

To get exactly thirty four!

**(ii)** For each day of the week

Make an account from me

If you make no mistake

You will get twenty three!

**(iii)** I am a special number

Take away from me a six!

A whole cricket team

You will still be able to fix!

**(iv)** Tell me who I am

I shall give a pretty clue!

You will get me back

If you take me out of twenty-two!

Solution.

**(i)** Let the required number be x.

Number of corners of the square = 4

Number obtained on counting every comer thrice = 4 x 3=12

According to the question, x + 12 = 34 ⇒ x = 34 -12 = 22

Hence, I am 22.

**(ii)** Let the required number be x.

Number of players in a cricket team = 11

According to the question.

x – 6 = 11 ⇒ x =11+6=17

Hence, lam 17.

**(iii)** Let the required number be v.

Number of days of a week = 7

According to the question.

x + 7 = 23 ⇒ x = 23-7 =16

Hence, lam 16.

**(iv)** Let the required number be x.

According to the question.

22 – x = x ⇒ x + x = 22

2x = 22 ⇒ x = 102 = 11

Hence, lam 11.