1.1 The Concept of Numbers (Counting)
There are many ways in which we can count. For example:
1, 2, 3, 4, ......Counting ones
2, 4, 6, 8, ......Counting twos
5, 10, 15, 20, ......Counting fives
20, 40, 60, 80, ......Counting twenties
- You can start counting from any number.
- You can also count backwards.
- What is the greatest number you know?
- Can we count to the last number?
1
- Write the missing numbers, and complete the pattern.
A- 74, 76, 78,
80 ,
82 ,
84
D- 30, 80, 130,
180 ,
230 ,
280
B- 105, 110, 115,
120 ,
125 ,
130
E- 421, 424, 427,
430 ,
433 ,
436
C- 800, 700,
600 ,
500 ,
400
F- 950, 900,
850 ,
800 ,
750
Even Numbers:
The numbers that are divisible by 2 are called even numbers,
like 2, 4, 6.
Odd Numbers:
The numbers that are not divisible by 2 are called odd numbers
like 3, 5, 9.
1- Write:
- The even numbers between 12 and 19:
14, 16, 18
- The odd numbers between 26 and 36:
27, 29, 31, 33, 35
- The first 6 even numbers after 37:
38, 40, 42, 44, 46, 48
2- Write 'E' for even numbers and 'O' for odd numbers:
47O
389O
255O
366E
148E
149O
152E
596E
3- Reasoning:
- Is 65 an even number? How do you know?
No, it is an Odd number. (Because it ends with 5, which is not divisible by 2).
- Is 41440 an even number? How do you know?
Yes, it is an Even number. (Because it ends with 0, which is divisible by 2).