If you hit a wall with the prime-number treatment, you can also just make a list.
The LCM of a and 12 is 36. So, a is definitely a factor of 36.
Try all the factors of 36, and see which ones actually work. The factors of 36 are 1, 2, 3, 4, 6, 9, 12, 18, and 36.
* The LCM of 1 and 12 is 12, not 36.
* The LCM of 2 and 12 is 12, not 36.
* The LCM of 3 and 12 is 12, not 36.
* The LCM of 4 and 12 is 12, not 36.
* The LCM of 6 and 12 is 12, not 36.
* The LCM of 9 and 12 is 36. a = 9 is an acceptable value.
* The LCM of 12 and 12 is 12, not 36.
* The LCM of 18 and 12 is 36. a = 18 is an acceptable value.
* The LCM of 36 and 12 is 36. a = 36 is an acceptable value.
So, 9, 18, and 36.
Ron has been teaching various standardized tests for 20 years.
--
Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
--
Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
--
Learn more about ron