RD Sharma Solutions Class 6 Knowing Our Numbers Exercise 1.7

RD Sharma Solutions Class 6 Chapter 1 Exercise 1.7

RD Sharma Class 6 Solutions Chapter 1 Ex 1.7 PDF Free Download

Exercise 1.7

Q1. Estimate the following by rounding off each factor to nearest hundreds:

i) 730 + 998

ii) 796 – 314

iii) 875 – 384

Sol :

i) 700 + 1000 = 1700

ii) 800 – 300 = 500

iii) 900 – 400 = 500

Q2. Estimate the following by rounding off each factor to nearest thousands:

i) 12904 + 2888

ii) 28292 – 21496

Sol :

i) 13000 + 3000 = 16000

ii) 28000 – 21000 = 7000

Q3. Estimate the following by rounding off each number to its greatest place:

i) 439 + 334 + 4317

ii) 8325 – 491

iii) 108734 – 47599

iv) 898 x 785

v) 9 x 795

vi) 87 x 317

Sol :

i) 400 + 300 + 4000 = 4700

ii)8000 – 500 = 7500

iii)100000 -500000 = 50000

iv) 900 x 800 = 720000

v) 10 x 800 = 8000

vi) 90 x 300 = 27000

Q4. Find the estimated quotient for each of the following by rounding off each number to its greatest place :

i) \(878 \div 28\)

ii) \(745 \div 24\)

iii) \(4489 \div 394\)

Sol :

i) \(900 \div 30\) = 30

ii) \(700 \div 20\) = 35

iii) \(4000 \div 400\) = 10

Exercise 1.8

Q1. Write the expression for each of the following statements using brackets :

i) Four multiplied by the sum of 13 and 7

ii) Eight multiplied by the difference of four from nine.

iii) Divide the difference of twenty eight and seven by 3.

The sum of 3 and 7 in multiplied by the difference of twelve and eight.

Sol :

i)4 x ( 13 + 7 )

ii)8 x ( 9 – 4 )

iii)\(\frac{28 – 7 }{ 3 }\)

iv) ( 3 + 7 ) x ( 12 – 8 )

Q2. Simplify each of the following :

i)124 – ( 12 – 2 ) x 9

ii) ( 13 + 7 ) x ( 9 – 4 ) – 18

iii) 210 – ( 14 – 4 ) x ( 18 + 2 ) – 10

Sol :

i) 34

ii) 82

iii) 0

Exercise 1.9

Q1) Simplify each of the following :

i) 7 x 109

ii) 6 x 112

iii) 9 x 105

iv) 17 x 109

v) 16 x 108

vi) 12 x 105

vii) 102 x 103

viii) 101 x 105

ix) 109 x 107

Sol :

i) 763

ii) 672

iii) 945

iv) 1853

v) 1728

vi) 1260

vii) 10506

viii)10605

ix)11663

Exercise 1.10

Q1) Write the roman – numerals for each of the following:

i) 33

ii) 48

iii) 76

iv) 95

Sol :

i) XXXIII

ii) XLVIII

iii) LXXVI

iv) XCV

Q2) Write the following in roman numerals:

i) 154

ii) 173

iii) 248

iv) 319

SOL :

i) CLIV

ii) CLXXIII

iii) CCXLVIII

iv) CCCXIX

Q3) Write the following in roman numerals:

i) 1008

ii) 2718

iii) 3906

iv) 3794

SOL :

i) KVIII

ii) KKDCCXVIII

iii) KKKCKVI

iv) KKKDCCXCIV

Q4) Write the following in roman numerals :

i) 4201

ii) 10009

iii) 44000

iv) 25819

SOL :

i) \(\bar{IV}CCI\)

ii) \(\bar{X}IX\)

iii) \(\bar{ XLIV }\)

iv) \(\bar{XXV}DCCCXIX\)

Q5) Write the following in Hindu – Arabic numerical:

i) XXVI

ii) XXIX

iii) LXXII

iv) XCI

SOL :

i) 26

ii) 29

iii) 72

iv) 91

Q6) Write the corresponding Hindu – Arabic numerical for each of the following :

i) CIX

ii) CLXXII

iii) CCLIV

iv) CCCXXIX

SOL :

i) 109

ii) 172

iii) 254

iv) 329

Q7) Write the corresponding Hindu – Arabic numerical for each of the following :

i) KXIX

ii) KDLXV

iii) KKCXXIII

iv) KKKDCXL

SOL :

i) 1019

ii) 1565

iii) 2123

iv) 3640

Q8)Write the following in Hindu – Arabic numerical :

i) \(\bar{IV}CDXLIV\)

ii) \(\bar{VI}CKXLIX\)

iii) \(\bar{IX}CCCXCI\)

iv) \(\bar{LX}XIX\)

SOL :

i) 4444

ii) 6949

iii) 9391

iv) 70009

Q9) Which of the following is meaningless ?

i) \(\bar{III}CC\)<

ii) KKKCCXI

iii) XD

iv) VC

SOL : (i) and (iii) are meaningless.


Practise This Question

After recording the height and weight, Ted wanted to know who is taller? Him or Ned. For that, he asked Ned’s height. He told that it was 135 cm and Ted’s height was 4.5 ft. Given 1 foot = 0.3 meters, what will be the value of Neds heightTeds height?