2, 1, 1/2, 1/4...
a. arithmetic
b. geometric
c. both
d. neither
Is it d? Thanks!
5 answers
Or is it b...
b is right. Each number is 1/2 of the previous number.
Thanks you, Ms. Sue. You're sure are a great help.
You are welcome, Chrisley. :-)
Actually, all the answers given (a, b, c, d) are wrong.
The correct answer should be
e. CANNOT BE DETERMINED
For a, an arithmetic sequence refers to a sequence that the difference between consecutive terms ((n+1)th term - nth term) is constant. Obviously 1-2 =/= 1/2-1
a is wrong
Thus, c is wrong.
For b, a geometric sequence refers to a sequence that the ratio between consecutive terms i.e. (n+1)th term/nth term is constant. Although the given four terms, such ratio is constant, i.e. 1/2=1/2/1=1/4 / 1/2, the fifth term is not given and you cannot know the general term of the sequence and thus the GENERAL ratio of the sequence.
So, it CANNOT be determined if b is correct if the GENERAL TERM of the sequence is NOT GIVEN and so as d.
Therefore, the answer is e, i.e. CANNOT BE DETERMINED.
(Point to note: You can ONLY determine if a sequence is arithmetic or geometric by knowing its GENERAL TERM and test if the common difference or ratio is CONSTANT.
The correct answer should be
e. CANNOT BE DETERMINED
For a, an arithmetic sequence refers to a sequence that the difference between consecutive terms ((n+1)th term - nth term) is constant. Obviously 1-2 =/= 1/2-1
a is wrong
Thus, c is wrong.
For b, a geometric sequence refers to a sequence that the ratio between consecutive terms i.e. (n+1)th term/nth term is constant. Although the given four terms, such ratio is constant, i.e. 1/2=1/2/1=1/4 / 1/2, the fifth term is not given and you cannot know the general term of the sequence and thus the GENERAL ratio of the sequence.
So, it CANNOT be determined if b is correct if the GENERAL TERM of the sequence is NOT GIVEN and so as d.
Therefore, the answer is e, i.e. CANNOT BE DETERMINED.
(Point to note: You can ONLY determine if a sequence is arithmetic or geometric by knowing its GENERAL TERM and test if the common difference or ratio is CONSTANT.
1 answer