## RD Sharma Solutions Class 6 Chapter 1 Exercise 1.2

#### Exercise 1.2

**Q1) Write each of the following numbers in digits by using international place value chart. Also, write them in expanded form.**

**i) Seven million three hundred three thousand two hundred six**

**Solution:Â **The number is expanded as = 7 x 1,000,000 + 3 x 100,000 + 0 x 10,000 + 3 x 1,000 + 2 x 100 + 0 x 10 + 6 x 1

**=Â **7,303,206

**ii) Fifty five million twenty nine thousand seven**

**Solution:Â **The number is expanded as = 5 x 10,000,000 + 5 x 1,000,000 + 0 x 100,000 + 2 x 10,000 + 9 x 1,000 + 0 x 100 + 0 x 10 + 7 x 1

=Â 55,029,007

**iii) Six billion one hundred ten million three thousand seven**

**Solution: **The number is expanded as = 6 x 1,000,000,000 + 1 x 100,000,000 + 1 x 10,000,000 + 0 x 1,000,000 + 0 x 100,000 + 0 x 10,000 + 3 x 1,000 + 0 x 100 + 0 x 10 + 7 x 1

= 6,110,003,007

**Q2) Rewrite each of the following numerals with proper commas in the international system of numeration**

**i) 513625**

**Solution:** By using the commas to separate periods the numeralÂ 513625 can be written asÂ 513,625 and is read as “Five hundred thirteen thousand six hundred twenty five”.

**ii) 4035672**

**Solution:** By using the commas to separate periods the numeralÂ 4035672Â can be written asÂ 4,035,672 and is read as “Four million thirty five thousand six hundred seventy two”.

**iii) 65954923**

**Solution:** By using the commas to separate periods the numeral 65954923 can be written as 65,954,923 and is read as “Sixty five million nine hundred fifty four thousand nine hundred twenty three”.

**iv) 70902005**

**Solution:** By using the commas to separate periods the numeral 70902005 can be written as 70,902,005 and is read as “Seventy million nine hundred two thousand five”.

**Q3) Write each of the following numbers in the international system of numeration:**

**i) Forty three lakh four thousand eighty four.**

**Solution:**Â “Forty three lakh four thousand eighty four” can be written in Indian SystemÂ of numeration as 43,04,084.

In International system of numeration it can be written as

4,304,084

This is read as “Four million three hundred four thousand eighty four”.

**ii) Six crore thirty four lakh four thousand forty four.**

**Solution:Â **“Six crore thirty four lakh four thousand forty four” can be written in Indian SystemÂ of numeration as 6,34,04,044.

In International system of numeration it can be written as

63,404,044

This is read as “Sixty three million four hundred four thousand forty four”.

**iii) Seven lakh thirty five thousand eight hundred ninety nine only.**

**Solution: **“Seven lakh thirty five thousand eight hundred ninety nine”Â can be written in Indian SystemÂ of numeration as 7,35,899.

In International system of numeration it can be written a

735,899

This is read as “Seven hundred thirty five thousand eight hundred ninety nine”.

**Q4) Write the following numbers in the Indian system of numeration:**

**i) Six million five hundred forty three thousand two hundred ten.**

**Solution:** The given number can be written in digits as 6,543,210

In the Indian System of numeration it can be written asÂ 65,43,210.

It is read as “Sixty five lakh forty three thousand two hundred ten”.

**ii) Seventy six million eighty five thousand nine hundred eighty seven**

**Solution:Â **The given number can be written in digits as 76,085,987

In the Indian System of numeration it can be written as 7,60,85,987

It is read as “Seven crore sixty lakh eighty five thousand nine hundred eighty seven”.

**iii) Three hundred twenty five million four hundred seventy nine thousand eight hundred thirty eight.**

**Solution:Â **The given number can be written in digits as 325,479,838.

In the Indian System of numeration it can be written asÂ 32,54,79,838.

It is read as “Thirty two crore fifty four lakh seventy nine thousand eight hundred thirty eight”.

**Q5) A certain nine digit number has only ones in ones period, only twos in the thousands period and only threes in millions period. Write this number in words in the Indian system.**

**Solution:** It is given that;

Only 1 inÂ ones period

Only 2 inÂ thousands period

Only 3 inÂ thousands period

Thus the number is 333,222,111

In Indian system, the number is written as 33,32,22,111 which is read as “thirty three crore thirty two lakh twenty thousand one hundred and eleven”.

**Q6) How many thousands make a million ?**

**Solution: **One Thousand = 1,000

One Million = 1,000,000

No. of thousands make a million = One Million/One Thousand = 1,000,000/1,000 = 1,000

â‡’ 1,000 thousands makes a million.

**Q7) How many millions make a billion ?**

**Solution: **One Million = 1,000,000

One Billion = 1,000,000,000

No. of millions make a billion = One Billion/One Million = 1,000,000,000/1,000,000 = 1,000

â‡’ 1,000 millions make a billion.

**Q8) (i) How many lakhs make a million?**

**Solution:** One Lakhs = 1,00,000

One Million = 1,000,000

No. of lakhs make a million = One Million/One Lakhs = 1,000,000/1,00,000 = 10

â‡’ 10 lakhs make a million.

**ii) How many lakhs make billion?**

**Solution:Â **One Lakhs = 1,00,000

One Billion = 1,000,000,000

No. of lakhs make a billion = One Billion/One Lakhs = 1,000,000,000/1,00,000 = 10,000

â‡’ 10,000 lakhs make a billion.

**Q9) Write each of the following in numerical form :**

**i) Eight million seven hundred eight thousand four.**

**Solution:Â **The number is expanded as = 8 x 1,000,000 + 7 x 100,000 + 0 x 10,000 + 8 x 1000 + 0 x 100 + 0 x 10 + 4 x 1

= 8,708,004

**ii) Six hundred seven million twelve thousand eighty four.**

**Solution:Â **The number is expanded as = 6 x 100,000,000 + 0 x 10,000,000 + 7 x 1,000,000 + 0 x 100,000 + 1 x 10,000 + 2 x 1000 + 0 x 100 + 8 x 10 + 4 x 1

= 607,012,084

**iii) Four billion twenty five million forty five thousand.**

**Solution:Â **The number is expanded as = 4Â x 1,000,000,000 + 0 x 100,000,000 + 2 x 10,000,000 + 5 x 1,000,000 + 0 x 100,000 + 4 x 10,000 + 5 x 1000 + 0 x 100 + 0 x 10 + 0 x 1

= 4,025,045,000

**Q10) Write the number names of each of the following in international system of numeration:**

**i) 435,002**

**Solution:**Â Four hundred thirty five thousand and two.

**ii) 1,047,509**

**Solution:Â **One million, forty-seven thousand, five hundred and nine

**iii) 59,064,523**

**Solution:Â **Fifty-nine million, sixty-four thousand, five hundred and twenty-three

**iv) 25,201,905**

**Solution:Â **Twenty-five million, two hundred one thousand, nine hundred and five