Class 3 Number System Tutorial
Warm-up
of Class 2
Example
1: Write the number
names of the following numbers.
a. 487 b. 630 c. 194 d.
708
Solution:
a. 487 =
Four hundred eighty-seven
b. 630 = Six
hundred thirty
c. 194 = One
hundred ninety-four
d. 708 =
Seven hundred eight
Example
2: Write the
following numbers in their expanded forms.
a. 507 b. 258 c. 619 d.
395
Solution:
a. 507 = 500 + 7
b. 258 = 200 + 50 + 8
c. 619 = 600 + 10 + 9
d. 395 = 300
+ 90 + 5
Example
3: Write the place
value of the underlined digits.
a. 398 b. 502 c. 827 d. 604
Solution: Place Value
a. 398 90
b. 502 500
c. 827 7
d. 604 0
Example
4: Write the
following numbers in ascending order.
a. 388, 294,
403, 198 b. 730,
528, 376, 504
c. 284, 581,
703, 462 d. 619,
382, 485, 518
Solution:
Ascending order
means the smallest to the greatest.
a. 198, 294,
388, 403 b. 376,
504, 528, 730
c. 284, 462,
581, 703 d. 382,
485, 518, 619
Introduction
to Numbers Up to 9999
In class 2,
you have studied the numbers up to 999. The greatest 3-digit number is 999.
When 1 is added to it, we get 1000.
999 + 1 =
1000
It is read
as one thousand. It is the smallest 4-digit number.
1000 is
equal to ten hundreds.
So, 10
hundreds = 1 thousand or 1000
When 1 is
added to 1000, we get 1001. It is read as one thousand one.
The greatest
4-digit number is 9999.
The numbers
starting from 1000 and ending till 9999 are called 4-digit numbers.
Here, you
will study about 4-digit numbers.
Number
Names
We know that
1000 = One thousand
Similarly,
2000 = Two thousand
3000 = Three
thousand
4000 = Four
thousand, …
Let us see
the number names of the following numbers:
6482 = Six
thousand four hundred eighty-two
4480 = Four
thousand four hundred eighty
9039 = Nine
thousand thirty-nine
7451 = Seven
thousand four hundred fifty-one
Place
Value and Face Value
The place
value of a digit in a number is defined by the position of that digit in
the number.
We have four
places in a 4-digit number, namely, ones (O), tens (T), hundreds (H) and
thousands (Th).
Therefore,
the place values of each digit in 5836 are 5 thousands, 8 hundreds, 3 tens and
6 ones, respectively.
Let us write
the place values of the underlined digits in the following numbers.
4873: Place value of 4 is 4000.
6921:
Place value of 9 is 900.
7408:
Place value of 0 is 0.
1036:
Place value of 6 is 6.
The face
value of a digit is the digit itself.
Examples: The face value of 6 in 3756 is 6.
The face
value of 5 in 2354 is 5.
The face
value of 8 in 4861 is 8.
The face
value of 2 in 2784 is 2.
Expanded
Forms of Numbers
When we
write a number as the sum of the place values of its digits in order, then it
is called the expanded form of the number.
Example: The expanded form of 5328 is 5000 +
300 + 20 + 8.
The expanded
form of 4921 is 4000 + 900 + 20 + 1.
The expanded
form of 7314 is 7000 + 300 + 10 + 4.
The expanded
form of 3232 is 3000 + 200 + 30 + 2.
Successor
and Predecessor of Numbers
The number which
comes just after a given number is called the successor of that number.
Examples:
The successor of 10
is 11.
The
successor of 125 is 126.
The
successor of 280 is 281.
The
successor of 2589 is 2590.
The number which
comes just before a given number is called the predecessor of that
number.
Examples: The predecessor of 20 is 19.
The
predecessor of 151 is 150.
The
predecessor of 267 is 266.
The
predecessor of 5376 is 5375.
Comparison
of Numbers
To compare
any two numbers, count the number of digits in both the numbers. The number
having greater number of digits is greater.
Example: Compare 946 and 1638.
1638 > 946
[1638 has 4 digits, and 946 has 3
digits]
If the
numbers have the same number of digits, then compare the digits at the highest
place. If these two digits are the same, then compare the digits in the next
highest place, and so on.
Example 1: Compare 5034 and 2769.
Solution:
Here, 5034 >
2769, because 5 > 2.
Example
2: Compare 3805 and
3592.
Solution: Here, 3 = 3, but 8 > 5. So, 3805
> 3592.
Example
3: Compare 2418 and
2463.
Solution: Here, 2 = 2 and 4 = 4, but 1 < 6.
So, 2418 < 2463.
Ordering
of Numbers
We can order
the numbers in ascending order or descending orders.
Ascending
Order
When the
numbers are arranged from the smallest to the greatest, then this order is
called ascending order.
Consider the
numbers: 2981, 1846, 9863 and 5143
Descending
Order
When the
numbers are arranged from the greatest to the smallest, then this order is
called descending order.
Consider the
numbers: 2981, 1846, 9863 and 5143
Forming
Greatest Numbers and Smallest Numbers
Greatest
Numbers
To form the
largest 4-digit number, arrange the given digits in descending order.
Example: The greatest 4-digit number that can
be formed using the digits 5, 3, 8 and 1 is 8531.
Smallest
Numbers
To form the
smallest 4-digit number, arrange the given digits in ascending order.
Example: The smallest 4-digit number that can
be formed using the digits 2, 7, 4 and 6 is 2467.
If 0 is one
of the digits, then we put 0 in the second position and next smallest number in
the first position.
Example: The smallest 4-digit number that can
be formed using the digits 8, 0, 3 and
4 is 3048.
Even and
Odd Numbers
Numbers that
can be divided into exact groups of twos are called even numbers.
Or, we can
say, numbers that end with 0, 2, 4, 6 or 8 are called even numbers.
Numbers that
cannot be divided into exact groups of twos are called odd numbers. Or, we can
say, numbers that end with 1, 3, 5, 7 or 9 are called odd numbers.
Class 3 Number System Test
Maths
Quiz for Class 3 Number System
Class 3 Number System Worksheet