Respuesta :

danimccrth
⇒ common ratio =r=3 and the given sequence is geometric sequence. Where an is the nth term, a is the first term and n is the number of terms. ⇒ 12th term is 708588 . ⇒Sum=1062880 .
sashamath28

Answer:

465

Step-by-step explanation:

The way I thought about it was I subtracted 30 from 15 and got 15. Then I subtracted 60 from 30 and got 20. My conclusion is you continue to add 5 more to what you added before. 15, 30, 60, 85, 115, 150, 190, 235, 285, 340, 400, 465.