Read the story and respond to the requests below.

Leo has $465 in a savings account. After one month, he has $530 in the account. The next month, the balance is $595. The balance after the third month is $660.

Write the sequence represented by the story.
Is the sequence arithmetic or geometric?
Does it have a common difference or common ratio?
What is the common difference or common ratio?
What are the next three terms?

1 answer

The sequence represented by the story is:

  1. $465 (initial amount)
  2. $530 (after one month)
  3. $595 (after two months)
  4. $660 (after three months)

To identify whether the sequence is arithmetic or geometric, we will check the differences between consecutive terms:

  • From $465 to $530: $530 - $465 = $65
  • From $530 to $595: $595 - $530 = $65
  • From $595 to $660: $660 - $595 = $65

Since the differences between consecutive terms are the same ($65), this is an arithmetic sequence.

Now, we can identify that there is a common difference in this sequence.

The common difference is $65.

To find the next three terms, we will add the common difference of $65 to the last term ($660):

  1. Next term: $660 + $65 = $725
  2. Next term: $725 + $65 = $790
  3. Next term: $790 + $65 = $855

Therefore, the next three terms are:

  • $725
  • $790
  • $855