Even and Odd Numbers

Show your work for each problem.

1.
Which number is even?
1. a)23
2. b)14
3. c)31
4. d)17
Answer: 14
14 ends in 4, which is an even digit. The others (17, 23, 31) end in odd digits (7, 3, 1).
2.
Which number is odd?
1. a)100
2. b)26
3. c)45
4. d)88
Answer: 45
45 ends in 5, which is an odd digit. The others (26, 88, 100) end in even digits (6, 8, 0).
3.
Is 56 even or odd? Type 'even' or 'odd'.
Answer: even
56 ends in 6, and 6 is an even digit (0, 2, 4, 6, 8). So 56 is even.
4.
Is 83 even or odd? Type 'even' or 'odd'.
Answer: odd
83 ends in 3, and 3 is an odd digit (1, 3, 5, 7, 9). So 83 is odd.
5.
Determine if 124 is even or odd by looking at the last digit.
Answer: even
1. What is the last digit of 124? 4
2. Is 4 in the list of even digits (0, 2, 4, 6, 8)? yes
3. Is 124 even or odd? even
6.
Is 0 (zero) even or odd?
1. a)Even
2. b)Odd
3. c)Neither
4. d)Both
Answer: Even
0 is even! with no remainder. Also, 0 ends in 0, which is an even digit.
7.
What is ? Is the result even or odd? Type 'even' or 'odd'.
Answer: odd
. 11 ends in 1, which is odd. Remember: Even + Odd = Odd.
8.
You have 18 stickers to share equally between 2 friends. Can it be done fairly?
Answer: yes
1. What is the last digit of 18? 8
2. Is 18 even or odd? even
3. Can 18 be divided by 2 with no remainder? (yes/no) yes
4. How many stickers does each friend get? 9
9.
What is the result of adding two odd numbers?
1. a)Cannot be determined
2. b)Always odd
3. c)Always even
4. d)Sometimes even, sometimes odd
Answer: Always even
Odd + Odd = Even! Examples: , , . All results are even.
10.
Determine if is even or odd without calculating the exact sum.
Answer: even
1. Is 7 even or odd? odd
2. Is 9 even or odd? odd
3. What is Odd + Odd? even
4. So is even or odd? even
11.
Is 347 even or odd? Type 'even' or 'odd'.
Answer: odd
347 ends in 7. Since 7 is odd, 347 is odd. The hundreds and tens digits don't matter!
12.
A class has 25 students. Can they form pairs with no one left over?
Answer: no
1. What is the last digit of 25? 5
2. Is 25 even or odd? odd
3. Can an odd number be divided evenly by 2? (yes/no) no
4. Will someone be left without a partner? (yes/no) yes
13.
If you multiply an even number by an odd number, the result is:
1. a)Always zero
2. b)Always odd
3. c)Always even
4. d)Sometimes even, sometimes odd
Answer: Always even
Even Odd = Even! Examples: , , . All even!
14.
Is even or odd? Solve step by step.
Answer: odd
1. Is 4 even or odd? even
2. Is 8 even or odd? even
3. What is Even + Even? even
4. Is 3 even or odd? odd
5. What is Even + Odd? odd
15.
What is ? Is the result even or odd? Type 'even' or 'odd'.
Answer: odd
. Both 3 and 5 are odd, and Odd Odd = Odd. 15 ends in 5 (odd).
16.
Is even or odd?
Answer: even
1. What is the last digit of -12 (ignore the sign)? 2
2. Is 2 an even or odd digit? even
3. Does the negative sign change if a number is even or odd? no
4. Is even or odd? even
17.
You want to arrange 31 chairs in rows of 2. How many complete rows can you make, and how many chairs are left over?
Answer: 15 rows, 1 left over
1. Is 31 even or odd? odd
2. What is (whole number part)? 15
3. How many chairs are left over? 1
4. How many complete rows? 15