Knowing Our Numbers



NCERT Solution Exercise 1.1

Question (1) Fill in the blanks

(a) 1 lakh = _____ ten thousand

Answer

1 lakh = Ten ten thousand

(b) 1 million = ____ hundred thousand

Answer

1 million = 1000,000 (International System of Notation)

1 million = 10,00,000 (Indian System of Notation)

1 million = Ten hundred thousand Answer

(c) 1 crore = ____ ten lakh

Answer

1 crore = 1,00,00,000 (Indian System of Notationa)

= 10 × 10,00,000

Thus, 1 crore = Ten ten lakh Answer

(d) (c) 1 crore = ____ million

Answer

1 crore = 10,000,000 (International System of Notation)

= 10 × 10,00,000

Thus, 1 crore = Ten ten lakh Answer

(e) 1 million = ____ lakh

Answer

1 million = 10,00,000 (International System of Notation)

= 10 × 1,00,000

Thus, 1 crore = Ten lakh Answer

Question (2) Place commas correctly and write the numerals:

(a) Seventy three lakh seventy five thousand three hundred seven.

Answer: 73,75,307

(b) Nine crore five lakh forty one.

Answer 9,05,041

(c) Seven crore fifty two lakh twenty one thousand three hundred two

Answer 7,52,21,302

(d) Fifty eight million four hundred twenty three thousand two hundred two

Answer

58,423,202 (International System of Notation)

5,84,23,202 (Indian System of Notation)

Number Name: Five crore eighty four lakh twenty three thousand two hundred two (Indian System of Number name)

(e) Twenty three lakh thirty thousand ten

Answer: 23,30,010

Question (3) Insert commas suitabley and write the names according to Indian System Numeration:

(a) 87595762

Answer

Number after inserting commas: 8,75,95,762

Number Name: Eight crore seventy five lakh ninety five thousand seven hundred sixty two.

(b) 8546283

Answer

Number after inserting commas: 85,46,283

Number Name: Eighty five lakh forty six thousand two hundred eighty three

(c) 99900046

Answer

Number after inserting commas: 9,99,00,046

Number Name: Nine crore ninety nine lakh forty six

(d) 98432701

Number after inserting commas: 9,84,32,701

Number Name: Nine crore eighty four lakh thirty two thousand seven hundred one

Question (4) Insert commas suitably and write the names according to International System of Numeration.

(a) 78921092

Answer

78,921,092 (International System of Numeration.)

Number Name: Seventy eight million nine hundred twenty one thousand ninety two (International System of Numeration.)

(b) 7452283

Answer

7,452,283 (International System of Numeration.)

Number Name: Seventy million four hundred fifty two thousand two hundred eighty three (International System of Numeration.)

(c) 99985102

Answer

99,985,102 (International System of Numeration.)

Number Name: ninety nine million nine hundred eighty five thousand one hundred two (International System of Numeration.)

(d) 48049831

48,049,831 (International System of Numeration.)

Number Name: Forty eight million forty nine thousand eight hundred thirty one (International System of Numeration.)

Extra Information About Indian and International System of Numeration

Indian System of Numeration

Ones (one digit)

Tens (Two digits)

Hundreds (Three digits)

Thousands (Four digits)

Ten thousand (Five digits)

Lakh (Six digits)

Ten Lakh (Seven digits)

Crore (Eight digits)

Ten Crore (Nine digits)

Arab (Ten digits)

Ten Arab (Eleven digits)

Kharab (Twelve digits)

Ten Kharab (Thirteen digits)

Neel (Forteen digits)

Ten Neel (Fifteen digits)

Padm (Sixteen digits)

Ten Padm (Seventeen digits)

Shankh (Eighteen digits)

Ten Shankh (Nineteen digits)

Maha Shankh (Twenty digits)

International System of Numeration

Ones (One digits)

Tens (Two digits)

Thousands (Three digits)

Million (Six zeros; Seven digits)

Ten million (Seven zeros; Eight digits)

Billion (Nine zeros; Ten digits)

Ten Billion (Ten zeros; Eleven digits)

Trillion (Twelve zeros; Thirteen digits)