Hi im a bit confused about these questions here. I do not know where to start, but much help is appreciated.

Question 1

In an arithmetic sequence t4 + t5 + t6 = 300 and t15 + t16 + t17 = 201

Find t18

Question 2

In a geometric sequence t1 + t2 + t3 = 21 and t4 + t5 + t6 = 168

Find the squence

Thanks in advance =]