CBSE Class 6 Maths - Ch2 Whole Numbers - NCERT Ex 2.1 (#cbsenotes)(#ncertanswers)

Chapter 2: Whole Numbers  

NCERT Ex 2.1 

CBSE Class 6 Maths 

Q1: Write the next three natural numbers after 10999.

Answer:
10,999 + 1 = 11,000
11,000 + 1 = 11,001
11,001 + 1 = 11,002


Q2: Write the three whole numbers occurring just before 10001.

Answer:
10,001 – 1 = 10,000
10,000 – 1 = 9,999
9,999  – 1 = 9,998


Q3: Which is the smallest whole number?

Answer: ‘0’ (zero) is the smallest whole number.




Q4: How many whole numbers are there between 32 and 53?

Answer: 53 – 32 – 1 = 20

There are 20 whole numbers between 32 and 53.


Q5. Write the successor of :

(a) 2440701
(b) 100199
(c) 1099999
(d) 2345670

Answer:

(a) Successor of 2440701 is 2440701 + 1 = 2440702
(b) Successor of 100199 is 100199 + 1 = 100200
(c) Successor of 1099999 is 1099999 + 1 = 1100000
(d) Successor of 2345670 is 2345670 + 1 = 2345671


Q6: Write the predecessor of :
(a) 94
(b) 10000
(c) 208090
(d) 7654321

Answer:

(a) The predecessor of 94 is 94 – 1 = 93
(b) The predecessor of 10000 is 10000 – 1 = 9999
(c) The predecessor of 208090 is 208090 – 1 = 208089
(d) The predecessor of 7654321 is 7654321 – 1 = 7654320


Q7: In each of the following pairs of numbers, state which whole number is on the left of the other number on the number line. Also write them with the appropriate sign (>, <) between them.

(a) 530, 503
(b) 370, 307
(c) 98765, 56789
(d) 9830415, 10023001

Answer:
(a) 530 > 503;
∴ 503 appear on left side of 530 on number line.

(b) 370 > 307;
∴ 307 appear on left side of 370 on number line.

(c) 98765 > 56789;
∴ 56789 appear on left side of 98765 on number line.

(d) 9830415 < 10023001;
∴ 9830415 appear on left side of 10023001 on number line


Q8: Which of the following statements are true (T) and which are false (F) ?

(a) Zero is the smallest natural number.
(b) 400 is the predecessor of 399.
(c) Zero is the smallest whole number.
(d) 600 is the successor of 599.
(e) All natural numbers are whole numbers.
(f) All whole numbers are natural numbers.
(g) The predecessor of a two digit number is never a single digit number.
(h) 1 is the smallest whole number.
(i) The natural number 1 has no predecessor.
(j) The whole number 1 has no predecessor.
(k) The whole number 13 lies between 11 and 12.
(l) The whole number 0 has no predecessor.
(m) The successor of a two digit number is always a two digit number.


Answer:
(a) False (✗)
Reason: Natural numbers start with 1. The smallest number is 1.

(b) False (✗)
Reason: 399 - 1 = 398 is the predecessor.

(c) True (✔)
Reason: Whole numbers start with 0, it is the smallest whole number.

(d) True (✔)
Reason: 599 + 1 = 600

(e) True (✔)
Reason: Whole Numbers = 0 and Natural Numbers. (0, 1, 2, 3, 4...)

(f) False (✗)
Reason: Zero is a whole number but it is not a natural number.

(g) False (✗)
Reason: 10 - 1 = 9

(h) False (✗)
Reason: Zero(0) is the smallest whole number.

(i) True (✔)
Reason: 1 is the smallest natural number.

(j) False (✗)
Reason: 1 - 1 = 0 (whole number)

(k) False (✗)
Reason: 11 + 1 = 12, 12 + 1 = 13 ∴ 12 lies between 12 and 13.

(l) True (✔)
Reason: Zero is the smallest whole number.

(m) False (✗)
Reason: 99 + 1 = 100 (three digit number).