Question

Which of the following statements describes this sequence 1, 3, 9, 27

I this is an arithmetic sequence

II The common ratio for this sequence is 3

III the next term in the sequence is 54

IV The sequence can be described by the expression n+3

I and IV

I,II, and III

II

Answer 1

II The common ratio for this sequence is 3. this is not an arithmetic sequence because you need to multiply by 3 and arithmetic sequences you can only add and subtract. the next term would not be 54 because 27*3 is 81. n describes the nth term of the sequence. so if n was 1, 1+ 3 is for and we already know that the 1st term is equal to 1. Therefore, II is the correct answer.