Inez waters her plants every two days. she trims them every 15 days. she did both today. when will she do both again?

You want to find the LCM of 2 and 15 for this problem. Multiply them to find the LCM since there are no common factors (besides 1). Think of everything as numbers first if it is hard for you to comprehend the word problem. Inez waters them on day 2, day 4, day 6, and so on is the meaning of “every two days”. On the other hand, she trims them on day 15, day 30, day 45, etc. is the meaning of “every 15 days”. You are now actually finding the multiples of 15 and 2. The two tasks share a common day which is day 30 is the meaning of “she did both today”. The question, "When will she do both again?" is asking how far away the next common day will be which should be in another 30 days. Therefore, your LCM is 30