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What is How Do You Know If a Number is Even?
Grade Level:
Pre-School – Class 2
All domains without exception
Definition
What is it?
To know if a number is even, you simply check its last digit. If the last digit of a number is 0, 2, 4, 6, or 8, then the entire number is an even number. Even numbers can always be divided into two equal groups without any remainder.
Simple Example
Quick Example
Imagine you have 10 laddoos. Can you divide them equally between your two friends? Yes, each friend gets 5 laddoos. Since 10 can be divided equally by 2, 10 is an even number. If you had 11 laddoos, you couldn't divide them equally without one friend getting more, so 11 is not even.
Worked Example
Step-by-Step
Let's check if the number 74 is an even number.
1. Look at the last digit of the number 74.
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2. The last digit of 74 is 4.
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3. Remember the rule: if the last digit is 0, 2, 4, 6, or 8, the number is even.
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4. Since 4 is one of these digits, 74 is an even number.
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5. We can also check by dividing by 2: 74 ÷ 2 = 37, with no remainder. So, 74 is an even number.
Why It Matters
Knowing about even numbers helps us organise things efficiently, like distributing items or scheduling events. This skill is vital for careers in logistics, where you manage deliveries, or in event planning, where you might need to seat guests in pairs. Even computer programmers use this concept to sort data!
Common Mistakes
MISTAKE: Thinking a number is even just because its first digit is even, like 23. | CORRECTION: Always check the LAST digit of the number, not the first. For 23, the last digit is 3, which is not 0, 2, 4, 6, or 8, so 23 is not even.
MISTAKE: Confusing even numbers with odd numbers, especially when dealing with large numbers. | CORRECTION: Remember the simple rule: last digit is 0, 2, 4, 6, or 8 for even numbers. All other last digits (1, 3, 5, 7, 9) make the number odd.
MISTAKE: Forgetting that 0 is considered an even digit and therefore any number ending in 0 is even. | CORRECTION: 0 is a key even digit. Numbers like 10, 200, 5000 are all even because they end in 0.
Practice Questions
Try It Yourself
QUESTION: Is 35 an even number? | ANSWER: No
QUESTION: Which of these numbers are even: 42, 57, 80, 113? | ANSWER: 42 and 80
QUESTION: A bus has 68 seats. Can all seats be filled by passengers sitting in pairs? | ANSWER: Yes, because 68 is an even number (ends in 8), so 68 passengers can sit in 34 pairs.
MCQ
Quick Quiz
Which of the following numbers is an even number?
123
457
670
991
The Correct Answer Is:
C
Option C (670) is correct because its last digit is 0, which is one of the digits (0, 2, 4, 6, 8) that make a number even. The other options end in 3, 7, or 1, making them odd numbers.
Real World Connection
In the Real World
When you buy groceries, sometimes offers are 'Buy one, get one free' or 'Buy two, get one free'. To make sure you get the most out of these offers, especially for 'Buy one, get one free', you often need to buy an even number of items. For example, if you want 4 packets of biscuits, you'd buy 2 and get 2 free, making 4 (an even number) in total.
Key Vocabulary
Key Terms
EVEN NUMBER: A number that can be divided by 2 without any remainder. | ODD NUMBER: A number that leaves a remainder of 1 when divided by 2. | LAST DIGIT: The digit in the ones place of a number. | DIVISIBLE: Able to be divided by another number exactly, without a remainder.
What's Next
What to Learn Next
Great job understanding even numbers! Next, you should learn about 'What are Odd Numbers?' You'll see how odd numbers are the opposite of even numbers and how together they cover all whole numbers. Keep up the good work!
