is 89 prime or composite

prime
composite

if you can give me all the answers plz do

A=answer

1. Is 89 prime or composite, A: prime
2. Is 93 prime or composite, A: composite
3. 432 is divisible by.. A: 2 and 3
4. 75, A: 5 5 x 3
5. 40, A: 2 2 2 x 5
6. 91, A: 7 x 13
7. 24 and 78, A: 6
8. 23 and 115. A: 23
9. 12 and 64, A:4
10. 5(2x+3), A: 10x + 15

I originally got a 80, but I reviewed all correct answers , So you guys should get a 100!

If you want to appear super smart to your fellow grade 6's

show them "Sieve of Eratosthenes" which works like this:

If you want to test if a given number is prime, like your 89
first guess what the closest square root of 89 is
here √89 is between 9 and 10

so list all the numbers from 2 to 9
-- is 89 divisible by 2 ? obviously not, since it is not even
so in your list, cross out the 2 and all remaining multiples of 2,
so gone are 2, 4 6, 8
-- is 89 divisible by 3, the first available number in your list ?
NO, so cross out the 3 and all multiples of 3, so gone are 3, 6, 9
So the only numbers left in your list are the 5 and 7
-- is 89 divisible by 5 ?? , NO, it does not end in a 5 or 0, so cross it out.
-- is 89 divisible by 7, the only number left?? NO,

All your divisors are crossed out,
so 89 is a prime number.

Try it with larger numbers, remember your list only has to go as far as
the square root of the number.

Hi! If you need help look up some videos from the web on prime and composite here's some tips :

prime number: number greater than 1 that is not a product of two smaller natural numbers.
composite number: is a positive integer that can be formed by multiplying two smaller positive integers.

Hope it helps,
Jiskha Helping Teachers
Company number : 214-556-5480
© 2021

I need help plz help plz!!!

if you read my name you would know that is why I need help so PLZ HELP

PLZ I NEED ANSWERS

I need help cause I am also dum!!!!

does anyone have all the answers?

OMG TYSM I PASSED THE PRACTICE ILY

thanks bro :(