Question

which of the following best describes this sequence? {135, 45, 15, 5, ...} an arithmetic sequence with a common ratio of \\(\frac{1}{3}\\) a geometric sequence with a common difference of 3. an arithmetic sequence with a common difference of 3. a geometric sequence with a common ratio of \\(\frac{1}{3}\\)

Explanation:

Step1: Identify sequence type

Check if terms have common ratio:
$\frac{45}{135} = \frac{1}{3}$, $\frac{15}{45} = \frac{1}{3}$, $\frac{5}{15} = \frac{1}{3}$

Step2: Eliminate wrong options

Arithmetic sequences use common difference (not ratio), so eliminate yellow/orange. Purple confuses ratio/difference.

Answer:

D. A geometric sequence with a common ratio of $\frac{1}{3}$