146k views
3 votes
Find the seventh term of the following sequence?

1, 2, 4, ...

1. 64
2. 22
3. 12

User Amaal
by
5.9k points

1 Answer

3 votes

Answer: the correct option is option 1

Explanation:

The first 3 terms of the sequence are

1, 2, 4, ..

The rate at which each term is increasing is in geometric progression.

The expression for the nth term of geometric sequence is

Tn = ar^n-1

Tn = the nth term of the sequence

a = the first term of the sequence

r = common ratio

From the information given,

The common ratio is expressed as the ratio of a term to its previous consecutive term. It becomes

2/1 = 4/2 = 2. Therefore

r = 2

a = 1

We want to determine the 7th term. It becomes

T7 = 1×2^7-1

T7 = 2^6 = 64

The 7th term is 64

User Janos Vinceller
by
5.9k points