Solved Exercises on Odd and Even Numbers Activities in Grade 1

Master odd and even numbers through engaging activities: sorting, grouping, and pattern recognition with these 3 detailed exercises.

Solution: Exercises 1 to 3
1 Sorting numbers into odd and even groups
Exercise 1
Sort these numbers into two groups: 5, 8, 12, 15, 18, 21, 24, 27, 30. Put even numbers in one group and odd numbers in another.
Definition:

Sorting activity: The process of organizing numbers into categories based on their odd or even property.

Sorting method:
  1. Look at each number individually
  2. Check if the number is divisible by 2 (even) or not (odd)
  3. Alternatively, check if the last digit is even (0,2,4,6,8) or odd (1,3,5,7,9)
  4. Place each number in the appropriate group
Original List
5, 8, 12, 15, 18, 21, 24, 27, 30
Classification
O, E, E, O, E, O, E, O, E
Groups
Even: 8,12,18,24,30; Odd: 5,15,21,27
Step 1: Examine each number individually

Check each number for divisibility by 2: 5 (odd), 8 (even), 12 (even), etc.

Step 2: Apply the last digit rule

Sort based on last digit: 5 (odd), 8 (even), 2 (even), 5 (odd), 8 (even), 1 (odd), 4 (even), 7 (odd), 0 (even)

Step 3: Create separate groups

Even numbers: 8, 12, 18, 24, 30 (end in 0, 2, 4, 8)
Odd numbers: 5, 15, 21, 27 (end in 1, 5, 7)

Even: 8, 12, 18, 24, 30
Odd: 5, 15, 21, 27
Final answer:

Even numbers: 8, 12, 18, 24, 30
Odd numbers: 5, 15, 21, 27

Applied rules:

• Even numbers: Divisible by 2 with no remainder

• Odd numbers: Not divisible by 2 (remainder of 1)

• Last digit rule: Works for all numbers 1-100

2 Grouping objects to identify odd/even
Exercise 2
You have 17 marbles. Can you put them into pairs with none left over? Explain your answer using grouping.
Definition:

Grouping activity: Physically or mentally organizing objects into pairs to determine if a number is odd or even.

Number of Marbles
17
Grouping Process
17 ÷ 2 = 8 R1
Result
One marble left over
Step 1: Start with 17 marbles

We have 17 individual marbles to work with

Step 2: Form pairs

Make groups of 2: Marble 1 + Marble 2, Marble 3 + Marble 4, etc.

Step 3: Check for leftovers

After forming 8 pairs (16 marbles), 1 marble remains unpaired

17 is odd because 17 ÷ 2 = 8 remainder 1
Final answer:

No, you cannot put 17 marbles into pairs with none left over. There will be 1 marble left over, which means 17 is an odd number.

Applied rules:

• Even numbers: Can be perfectly divided into pairs (no remainder)

• Odd numbers: Cannot be perfectly divided into pairs (remainder of 1)

• Division rule: When dividing by 2, remainder 0 = even, remainder 1 = odd

3 Continuing number patterns
Exercise 3
Continue this pattern of even numbers: 2, 4, 6, 8, ___, ___, ___. Then continue this pattern of odd numbers: 1, 3, 5, 7, ___, ___, ___.
Definition:

Number pattern activity: Recognizing and continuing sequences of odd or even numbers.

Even Pattern
2, 4, 6, 8, 10, 12, 14
Odd Pattern
1, 3, 5, 7, 9, 11, 13
Rule
Add 2
Step 1: Identify the even number pattern

Looking at 2, 4, 6, 8 - each number is 2 more than the previous

Step 2: Continue the even number pattern

8 + 2 = 10, 10 + 2 = 12, 12 + 2 = 14

Step 3: Identify the odd number pattern

Looking at 1, 3, 5, 7 - each number is 2 more than the previous

Step 4: Continue the odd number pattern

7 + 2 = 9, 9 + 2 = 11, 11 + 2 = 13

Even: 2, 4, 6, 8, 10, 12, 14
Odd: 1, 3, 5, 7, 9, 11, 13
Final answer:

Even pattern: 2, 4, 6, 8, 10, 12, 14
Odd pattern: 1, 3, 5, 7, 9, 11, 13

Applied rules:

• Pattern recognition: Identify the consistent operation between consecutive numbers

• Even number pattern: Even numbers increase by 2 (2, 4, 6, 8, 10...)

• Odd number pattern: Odd numbers increase by 2 (1, 3, 5, 7, 9...)

Visual Infographic: Odd and Even Numbers Activities

Odd and Even Numbers Activities

Engaging Ways to Learn

1
2
3
4
5
6
7
8
9
10
→
2
Even
3
Odd
4
Even
5
Odd
Activity 1: Sorting
Group numbers into odd and even categories based on their properties.
Activity 2: Grouping
Organize objects into pairs to see if any are left over.
Activity 3: Patterns
Recognize and continue number sequences of odd and even numbers.
Activity 4: Games
Interactive games that reinforce odd/even number recognition.
Rules and methods, laws,...
\(n \div 2 = \text{whole number (even)}\)
Even Number Test
Even
\(n \div 2 = \text{no remainder}\)
Divisible by 2
Odd
\(n \div 2 = \text{remainder 1}\)
Not divisible by 2
Pattern
\(2, 4, 6... / 1, 3, 5...\)
Alternating sequence
Even numbers: Divisible by 2 with no remainder. End in 0, 2, 4, 6, 8.
Odd numbers: Not divisible by 2 (remainder of 1). End in 1, 3, 5, 7, 9.
Key Concepts: Odd and Even Numbers Activities
\(n \mod 2\)
Remainder Check
Key definitions:

Even number: A number that can be divided by 2 with no remainder

Odd number: A number that cannot be divided by 2 without a remainder

Activity-based learning: Using hands-on methods to understand mathematical concepts

Complete methodology:
  1. Identify the number: Look at the number you want to classify
  2. Apply the divisibility test: Divide by 2 and check for remainder
  3. Use the last digit method: Check if the last digit is even or odd
  4. Verify with grouping: Imagine pairing objects to confirm
Tip 1: Remember: even numbers end in 0, 2, 4, 6, or 8.
Tip 2: Odd numbers end in 1, 3, 5, 7, or 9.
Tip 3: Practice with physical objects to visualize pairing.
Tip 4: Odd and even numbers alternate: even, odd, even, odd...
Common errors: Misidentifying numbers ending in 0 as odd, forgetting the alternating pattern.
Practice tips: Start with numbers 1-10, then extend to larger numbers.
Key rules to remember:

• Even numbers: Divisible by 2 (remainder 0)

• Odd numbers: Not divisible by 2 (remainder 1)

• Last digit rule: Even numbers end in 0,2,4,6,8; odd numbers end in 1,3,5,7,9

• Alternating pattern: Even and odd numbers alternate in sequence

Questions & Answers

Question: Why do we need to know about odd and even numbers? When will I use this?

Answer: Learning about odd and even numbers is important because it builds foundational math skills! You'll use this knowledge:

  • When learning multiplication and division
  • To understand number patterns and sequences
  • When working with fractions and grouping
  • In real life: sharing items equally with friends

It also helps develop logical thinking and prepares you for more complex math concepts. Plus, it's fun to notice patterns in numbers everywhere!

Question: My child is struggling to understand the concept. How can I make it more tangible for them?

Answer: Making odd and even numbers tangible is key! Try these hands-on activities:

  • Use small toys, blocks, or candies to physically group into pairs
  • Draw circles or dots and connect them in pairs
  • Have your child count steps while walking, calling out "even" and "odd" alternately
  • Use a hundreds chart and color even numbers one color, odd another

The physical act of pairing objects helps children visualize the concept. Once they understand the idea with small numbers, gradually introduce larger numbers.

Question: What about zero? Is it odd or even?

Answer: Zero is an even number! This might seem surprising, but here's why:

Zero can be divided by 2 with no remainder: 0 ÷ 2 = 0 with remainder 0.

You can think of zero as "no groups of two," which still fits the definition of being divisible by 2. Zero also follows the pattern rule - it ends in 0, which is one of the even digits (0, 2, 4, 6, 8).

So remember: zero is definitely even!

Detailed Summary: Odd and Even Numbers Activities

Definitions

Even Numbers: Whole numbers that can be divided by 2 with no remainder. They can be perfectly paired or grouped into sets of 2.

Odd Numbers: Whole numbers that cannot be divided by 2 without a remainder. When grouped into pairs, there is always 1 left over.

Division Test: A number is even if dividing by 2 results in no remainder; odd if there's a remainder of 1.

Last Digit Rule: A quick way to identify odd/even numbers by looking at the final digit.

Core Rules and Laws
  • Even Rule: n ÷ 2 = whole number (no remainder), where n is even
  • Odd Rule: n ÷ 2 = whole number with remainder 1, where n is odd
  • Last Digit Rule: Even numbers end in 0, 2, 4, 6, or 8; odd numbers end in 1, 3, 5, 7, or 9
  • Alternating Pattern Rule: In counting order, even and odd numbers alternate (even, odd, even, odd...)
Step-by-Step Methods
  1. Identify the Number: Look at the number you want to classify
  2. Apply Division Test: Divide the number by 2 and check for remainder
  3. Use Last Digit Method: Check if the final digit is even (0,2,4,6,8) or odd (1,3,5,7,9)
  4. Visual Pairing: Imagine grouping objects into pairs to see if one is left over
  5. Verify Result: Double-check using a different method
Examples (Simple → Advanced)
Simple Example
Number 4: 4 ÷ 2 = 2 remainder 0 → Even
Number 5: 5 ÷ 2 = 2 remainder 1 → Odd
Intermediate Example
Number 12: Ends in 2 (even digit) → Even
Number 13: Ends in 3 (odd digit) → Odd
Advanced Example
Number 246: Ends in 6 (even digit) → Even
Number 357: Ends in 7 (odd digit) → Odd
Tips, Tricks, and Common Pitfalls
  • Tip 1: Remember the rhyme: "0, 2, 4, 6, 8 - being even is really great!"
  • Tip 2: Practice with physical objects like counters or toys to visualize pairing
  • Tip 3: Notice that even and odd numbers alternate in counting order
  • Pitfall 1: Thinking 0 is odd (zero is actually even: 0 ÷ 2 = 0 remainder 0)
  • Pitfall 2: Forgetting that the pattern alternates: even, odd, even, odd...
  • Pitfall 3: Misidentifying large numbers without checking the last digit
Key Notes for Memorization
  • Even numbers: 0, 2, 4, 6, 8 - they end in these digits
  • Odd numbers: 1, 3, 5, 7, 9 - they end in these digits
  • Even numbers can be perfectly paired (no leftovers)
  • Odd numbers always have one left over when pairing
  • Remember: 0 is even (not odd) because 0 ÷ 2 = 0 remainder 0
  • For any number, only the last digit matters for odd/even classification