Question

I need help to find the lcm of 12, 28, it is taking to long and i never get the right answer!

Answer 1

Becca

12 written as prime numbers is 2 * 2 * 3 do you understand this?

Answer 2

28 is 2 * 2 * 7

Answer 3

Uhhh not really....

Answer 4

How about this...
12 is 4 * 3
28 is 4 * 7

Answer 5

The LCM of 12 and 28 is 84.

Answer 6

Yea :V

Answer 7

I get that blexing

Answer 8

OK.. they both have a 4 so you only use it once.

You multiply all the things they have in common (4) times all the things they don't have in common (3 and 7)

SO... 4 * 3 * 7 = 84

Answer 9

Mhmm........... Why would you multiply 3 and 7 even though they dont have them in common? I am so difficult :( I don't understand anything....

Answer 10

You are ok... it is just the way you find the lcm. Do you have another one, I will help you.

Answer 11

Yea 12 & 19
90*

Answer 12

What is the 90*

12 = 3 * 4
19 = 1 * 19

so it is just 1 * 3 * 4 * 19 nothing in common which means it is actually 12*19

Answer 13

I meant 90 not 19 lol

Answer 14

I wasnt looking when i was typing

Answer 15

OK

12 = 2 * 2 * 3 (4 times 3)
90 = 2 * 5 * 9 (2 times 45 and 45 is 5 times 9)

Do you get this?

Answer 16

Yea I understand a llittle...... Im struggling in math so I hope i'm not bothering.....

Answer 17

OR
12 = 2 * 6
12 = 2 * 2 * 3 (I replaced the 6 with 2 * 3)

90 = 2 * 45
90 = 2 * 5 * 9 (I replaced the 45 with 5 * 9)
90 = 2 * 5 * 3 * 3 (I replaced the 9 with 3 * 3)

This is how it should look.. I forgot to break down the 9 in my last post

Answer 18

Oh now get it better!

Answer 19

12 = 2 * 2 * 3
90 = 2 * 5 * 3 * 3

What do they both have....... answer (2 and a 3)

So you multiply 2 * 3 (what they have in common) and then everything else

2 * 3 (common) * 2 * 5 * 3 (not common)
180

Answer 20

Oh okay I get that

Answer 21

Thx

Answer 22

Anymore?

Answer 23

Uhh 28, 42

Answer 24

28x3=84
42x2=84.

Your LCM is 84!