Prime or Composite?
Is 15 a prime number or a composite number?
Explain or show your reasoning.
15 is a composite number because 1x15 = 15 and 3x5 = 15.
Select all the true statements.
A. 4 is a factor of 20.
B. 6 is a factor of 20.
C. 5 is a factor of 20.
D. 8 is a factor of 20.
A and C
Select all the true statements.
A. 12 is a multiple of 3.
B. 14 is a multiple of 3.
C. 20 is a multiple of 4.
D. 25 is a multiple of 5.
A, C, and D.
There are 20 students in a class. They want to make equal groups of 4.
Can they make equal groups? Explain or show your reasoning.
Yes 20 is a multiple of 4.
4 x 5 = 20.
Is 23 a prime number or a composite number?
Explain or show your reasoning.
23 is a prime number because it only has one factor pair (1x23 = 23)
Select all the true statements.
A. 3 is a factor of 18.
B. 4 is a factor of 18.
C. 6 is a factor of 18.
D. 9 is a factor of 18.
A, C and D.
Select all the true statements.
A. 18 is a multiple of 6.
B. 21 is a multiple of 4.
C. 30 is a multiple of 4.
D. 35 is a multiple of 7.
A and D
A teacher has 35 stickers to give equally to 5 students.
Can each student get the same number of stickers?
Explain or show your reasoning.
Yes 35 is a multiple of 5.
5 x 7 = 35 OR 35 รท 5 = 7.
Is 32 a prime number or a composite number?
Explain or show your reasoning.
32 is a composite number because 1x32=32, 2x16=32, 4x8=32.
Find all factor pairs of 24.
1 and 24
2 and 12
3 and 8
4 and 6
Is 42 a multiple of 5?
Explain or show your reasoning.
No because 5, 10, 15, 20, 25, 30, 25, 40, 45.
A school has 47 markers. They want to put the markers equally into groups of 5.
Can they do this without any markers left over?
Explain or show your reasoning.
No because 47 is not a multiple of 5.
5, 10, 15, 20, 25, 30, 35, 40, 45, 50.
Is 51 a prime number or a composite number?
Explain or show your reasoning.
51 is a prime number because it has one factor pair (1x51=51).
Find all factor pairs of 48.
1 and 48
2 and 24
3 and 16
4 and 12
6 and 8
Which numbers are multiples of both 3 and 4?
A. 12
B. 18
C. 24
D. 30
A and C
A teacher has 36 books. She wants to put the books into equal groups of 3 or 4.
Can she do both? Explain or show your reasoning.
Yes 36 is a multiple of 3 and 4.
3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36
4, 8, 12, 16, 20, 24, 28, 32, 36