Whole Numbers Ex 2.1
Q1. Write the next three natural numbers after 10999.
Solutions:
The next three natural numbers after 10999 are 11000, 11001 and 11002
Q2. Write the three whole numbers occurring just before 10001.
Q2. Write the three whole numbers occurring just before 10001.
Solutions:
The three whole numbers occurring just before 10001 are 10000, 9999 and 9998
Q3. Which is the smallest whole number?
Solutions:
The smallest whole number is 0
Q4. How many whole numbers are there between 32 and 53?
Solutions:
The whole numbers between 32 and 53 are
(33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52)
Hence, there are 20 whole numbers between 32 and 53
(33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52)
Hence, there are 20 whole numbers between 32 and 53
Q5. Write the successor of:
(a) 2440701 (b) 100199 (c) 1099999 (d) 2345670
Solutions:
The successors are
(a) 2440701 + 1 = 2440702
(b) 100199 + 1 = 100200
(c) 1099999 + 1 = 1100000
(d) 2345670 + 1 = 2345671
Q6. Write the predecessor of:
(a) 94 (b) 10000 (c) 208090 (d) 7654321
Solutions:
The predecessors are
(a) 94 – 1 = 93
(b) 10000 – 1 = 9999
(c) 208090 – 1 = 208089
(d) 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
Solutions:
(a) Since, 530 > 503
Hence, 503 is on the left side of 530 on the number line
(b) Since, 370 > 307
Hence, 307 is on the left side of 370 on the number line
(c) Since, 98765 > 56789
Hence, 56789 is on the left side of 98765 on the number line
(d) Since, 9830415 < 10023001
Hence, 9830415 is on the left side of 10023001 on the number line
Q8. Which of the following statements are true (T) and which are false (F)?
(a) Zero is the smallest natural number.
Solution:
False
0 is not a natural number
(b) 400 is the predecessor of 399.
Solution:
False
The predecessor of 399 is 398 Since, (399 – 1 = 398)
Solution:
False
The predecessor of 399 is 398 Since, (399 – 1 = 398)
(c) Zero is the smallest whole number.
Solution:
True
Zero is the smallest whole number
Solution:
True
Zero is the smallest whole number
(d) 600 is the successor of 599.
Solution:
True
Since (599 + 1 = 600)
Solution:
True
Since (599 + 1 = 600)
(e) All natural numbers are whole numbers.
Solution:
True
All natural numbers are whole numbers
Solution:
True
All natural numbers are whole numbers
(f) All whole numbers are natural numbers.
Solution:
False
0 is a whole number but is not a natural number
Solution:
False
0 is a whole number but is not a natural number
(g) The predecessor of a two digit number is never a single digit number.
Solution:
False
Example the predecessor of 10 is 9
Solution:
False
Example the predecessor of 10 is 9
(h) 1 is the smallest whole number.
Solution:
False
0 is the smallest whole number
Solution:
False
0 is the smallest whole number
(i) The natural number 1 has no predecessor.
Solution:
True
The predecessor of 1 is 0 but is not a natural number
True
The predecessor of 1 is 0 but is not a natural number
(j) The whole number 1 has no predecessor.
Solution:
False
0 is the predecessor of 1 and is a whole number
Solution:
False
0 is the predecessor of 1 and is a whole number
(k) The whole number 13 lies between 11 and 12.
Solution:
False
13 does not lie between 11 and 12
Solution:
False
13 does not lie between 11 and 12
(l) The whole number 0 has no predecessor.
Solution:
True
The predecessor of 0 is -1 and is not a whole number
Solution:
True
The predecessor of 0 is -1 and is not a whole number
(m) The successor of a two digit number is always a two digit number.
Solution:
False
As the successor of 99 is 100
Solution:
False
As the successor of 99 is 100
