Question

Why are the divisibility rules for 2, 3, and 5 very useful for determining prime and composite numbers

1. They are the smallest odd numbers
2. They add up to 10
3. They are prime numbers with nice divisibility rules
4. They multiply to 30
5. They can be multiplied together to make every number

Answer 1

They are prime numbers with nice divisibility rules

Answer 2

option 3.

Explanation:

alright, ima explain each option.

1. "smallest odd numbers" 2 is an even number. that's out of the playing field.

2. "add up to 10" sure, they do add up to 10, but finding prime and composite numbers are all about division and multiplication.

3. this is true. 2, 3, and 5 are all prime numbers, and they have the nice divisibility rules. [ for 2, it has to be even, for 5, it has to end in 0 or 5, and 3 has to have the sum of its digits being divisible by 3. ]

4. they do multiply to 30, but this does not help break the composite numbers down.

5. we cannot make every number with just these. we can not multiply any other whole number to get 7 for per example, because it's a prime number.

sub to gauthmath sub reddit if ya can !