PRIME AND COMPOSITE NUMBERS

PRIME AND COMPOSITE NUMBERS

PRIME NUMBERS

A NUMBER WHICH HAS ONLY TWO FACTORS, (1 AND THE NUMBER ITSELF) IS A PRIME NUMBER

EG: 2,3,5,7,11,13........ARE SOME PRIME NUMBERS

COMPOSITE NUMBERS

A NUMBER WHICH HAS MORE THAN TWO FACTORS ARE COMPOSITE NUMBERS

EG: 4,6,8,9,10,12,14.........ARE COMPOSITE NUMBERS

SIEVE OF ERATOSTHENES

THIS METHOD IS USED TO FIND THE PRIME AND COMPOSITE NUMBERS BETWEEN 1 AND 100

PRIME NUMBERS BETWEEN 1 AND 100

2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71

73,79,83,89 AND 97

Multiple Choice

Is 3 a factor of 12?

• yes

• no

Multiple Choice

Which list has only prime numbers?

• 2, 3, 4, 5

• 1, 5, 7, 9

• 2, 3, 5, 7

• 2, 4, 6, 8

Multiple Choice

Which of the following numbers shows all of the factors of 12?

• 1,2,3,4,6,12
• 1,2,3,4,6,8,12
• 1,2,4,6,12
• 2,4,6,8,10,12

Multiple Choice

Which number is NOT divisible 6?

• 35

• 42

• 18

• 72

Multiple Choice

Which of the following equations will NOT result in a multiple of 5?

• 11 x 5 = _______
• 7 x 3 = _______
• 6 x 5 = _______
• 2 x 5 = _____

Multiple Choice

Which of the following is a factor of 54?

• 4

• 7

• 5

• 9

Multiple Choice

Find the prime number

• 10

• 9

• 7

• 4

Multiple Choice

Prime numbers have:

• Exactly 2 factors

• 2 pairs of factors

• More than 2 factors

• 1 factor

Multiple Choice

How is a prime number different from a composite number?

• Prime numbers are smaller than composite numbers.

• Composite numbers are larger than prime numbers.

• All odd numbers are prime numbers.

• Prime numbers have only 2 factors, and composite numbers have more than 2 factors.

Multiple Choice

Are all even numbers composite numbers?

• Yes

• No

Multiple Choice

Are there any numbers that are neither prime nor composite?

• Yes

• No

Multiple Choice

Which number is NOT a factor of 10?

• 1

• 2

• 3

• 5

Multiple Choice

Which number below is NOT prime?

• 2

• 11

• 13

• 18