Question

The question is:
identify each number as prime or composite.
(A) 321 (B) 87 (C) 93 (D) 53 (E) 105 and (F) 1,072
Please explain the process. I'm sure if I can get the process of (A) I will know the rest. :)

Answer 1

We need some definitions.

Definition: A prime number is a whole number with exactly two integral divisors, 1 and itself.

The number 1 is not a prime, since it has only one divisor.

So the smallest prime numbers are:

2, 3, 5, 7, ...

The number 4 is not prime, since it has three divisors (1, 2, and 4), and 6 is not prime, since it has four divisors (1, 2, 3, and 6).

Answer 2

ok

Answer 3

Is 321 a prime number? The number of prime numbers is infinite so you are not expected to memorize them. :) See if you can find a number that divides 321.

Answer 4

how would you go abouts trying the find number that goes into 321? would I divide something into 321?

Answer 5

Yes, I usually start with 2, 3, and then 5.

Answer 6

Ok. :) so like divide 2 into 321? Then do I have to see if it comes out evenly?

Answer 7

From Mathematica:
{ 321, 87 , 93, 53 , 105 , 1072} // PrimeQ
{False, False, False, True, False, False}

Answer 8

Yes. If that does not work, try 3. (Too bad I can't delete the interloper's post. Bad manners on his part. Just ignore it for now.)

Answer 9

Thank you! Will do. lol! :)

Answer 10

Click on the blue DRAW button and show the division of 3 into 321. We're not finished. Because the interloper posted answers does not mean that you know the process or that he does either, for that matter.

Answer 11

ok. :)
Just a min..