Question

Determine whether the sequence 7, 21, 35, 49 is geometric. If so, find its common

ratio.
Answer:
a. no
b. yes, common ratio of 14
c. yes, common ratio of 2

Answer 1

a. no

Explanation:

The sequence is arithmetic. It has a common difference of 14.

7 + 14 = 21

21 + 14 = 35

35 + 14 = 49

A geometric series has a common ratio (multiplication). For example:

7 × 3 = 21

21 × 3 = 63

63 × 3 = 189

Answer 2

B

Explanation: