In the given sequence, the bids are as follows:
205, 216, 227, 238, ...
To identify the arithmetic sequence, we first need to find the common difference (d).
Calculating the common difference:
- \(216 - 205 = 11\)
- \(227 - 216 = 11\)
- \(238 - 227 = 11\)
So, the common difference \(d\) is \(11\).
The formula for the \(n\)th term of an arithmetic sequence is given by:
\[ A(n) = A(1) + (n - 1) \cdot d \]
Where:
- \(A(1)\) is the first term of the sequence,
- \(d\) is the common difference,
- \(n\) is the term number.
Given:
- The first term \(A(1)\) is \(205\),
- The common difference \(d\) is \(11\).
Substituting these values into the formula:
\[ A(n) = 205 + (n - 1) \cdot 11 \]
Simplifying this:
\[ A(n) = 205 + 11n - 11 \]
\[ A(n) = 11n + 194 \]
So the rule to represent the arithmetic sequence is:
\[ A(n) = 11n + 194 \]
Now, to find the tenth bid (\(A(10)\)):
\[ A(10) = 11(10) + 194 \]
Calculating:
\[ A(10) = 110 + 194 = 304 \]
Thus, the tenth bid is \(304\).
Final answers:
- The rule for the arithmetic sequence is \(A(n) = 11n + 194\).
- The tenth bid is \(304\).