Exercise 3
1
Choose the correct option.
(i)
−5 is .........
a) a whole number
b) a natural number
c) an integer
d) a fraction
(ii)
−5
<
0
a) >
b) <
c) =
d) None of the above
Ans.
(i) (c) an integer
(ii) (b) <.
2
Write whether the following statements are True or False.
(i)
Zero is the smallest natural number.
(ii)
All natural numbers are whole numbers.
(iii)
All whole numbers are natural numbers.
(iv)
The sum of opposite numbers is zero.
Ans.
(i) False
(ii) True
(iii) False
(iv) True
Note:
For 2(iv), the answer given in the textbook is incorrect.
3
Write the following four numbers in ascending order.
87,29,35,104
87,39,27,401
85,93,21,793
89,51,23,307
Ans. Ascending order:
85,93,21,793
87,29,35,104
87,39,27,401
89,51,23,307
4
Obtain five-digit numbers using the digits 1 to 9 only once.
Read them and write them in words and write the largest and
smallest numbers.
Ans.
(i)
24,681
Twenty four thousand six hundred eighty one.
(ii)
35,792
Thirty five thousand seven hundred ninety two.
(iii)
46,135
Forty six thousand one hundred thirty five.
(iv)
98,754
Ninety eight thousand seven hundred fifty four.
Largest among these numbers
98,754
Smallest among these numbers
24,681
Important Note
The largest and smallest numbers above are the largest
and smallest among the four numbers obtained.
If we have to form the largest possible five-digit
number using digits 1 to 9 without repeating any
digit, the number is 98,765.
The smallest possible five-digit number
is 12,345.
5
Answer the following questions.
(i)
Draw a number line on your notebook and show the
numbers −5, 3, −3 and 7 on it.
Number line
(ii)
What are the numbers to the right of zero called?
Ans. (ii)
Positive numbers.
(iii)
What are the numbers to the left of zero called?
Ans. (iii)
Negative numbers.
6
A district spent ₹ 69,27,762 in the financial year
2023-24 and ₹ 88,36,584 in the financial year
2024-25 for environmental protection. What is the
total expenditure for environmental protection in
these two financial years? How much more money was
spent in 2024-25 than 2023-24?
Solution
(i) Expenditure of 2023-24 +
Expenditure of 2024-25
Total = ₹ 1,57,64,346
(ii) Expenditure of 2024-25 −
Expenditure of 2023-24
Difference = ₹ 19,08,822
Ans.
(i) Total expenditure in two years :
₹ 1,57,64,346.
(ii) ₹ 19,08,822 more was spent in 2024-25 than 2023-24.
(ii) ₹ 19,08,822 more was spent in 2024-25 than 2023-24.
7
Write the numbers 1 to 9 in the given box in such
a way that each number appears only once and their
vertical, horizontal and diagonal sums are equal.
8
1
6
3
5
2
Ans.
Write the numbers 1 to 9 so that the vertical,
horizontal and diagonal sums are equal.
8
1
6
3
5
7
4
9
2
Vertical, horizontal and diagonal sums are equal.
Each sum = 15
Each sum = 15