Download EXPTORE: Primes and Composites 2x6:12

EXPTORE: Primes and Composites
Write whether each number is prime or composite.
Give an example to show why the nurnber is composite.
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27
2.
31
3. 35
4.
51
5. 59
6. 80
7-
73
8. 49
9.
61
Whole numbers greater than 1 are either prime numbers or composite numbers.
prime number has only 2 factors: 1 and itself.
A composite number has more factors than 1 and itself.
A
ls 7 prime or composite?
Step
I
Step 2
Find the factors. 1 x 7 : 7
The only factors of 7 are 1 and 7.
Compare the factors with the
definitions. 7 is a prime number.
1X7:7
ls 12 prime or composite?
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Step 2
Find the factors. 2 x 6
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12 has several factors.
:
12:12,3X4:12
12,
Compare the factors with the definitions.
12 is a composite number.
Rememben /ou can use basic facts, unit cubes, or
graph paper to help you find factors.
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1X12:12
2x6:12
Explore: Primes and Composites
Find a path from Star Base Alpha to Star Base Beta through the meteor shower.
The only safe path is through the prime numbers.
O Silver BurdefrGinn
lnc
G29)
Use with Grade 5, to<t pages
334-335.