Consider the geometric series: \( 45+15+5+\ldots \) 3.1 Does the sequence converge or diverge? Justify your answe 3.2 Determine the sum to infinity of the series, if it exists.
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This geometric series converges because the common ratio \( r \) can be found by dividing the second term by the first term: \( r = \frac{15}{45} = \frac{1}{3} \). Since \( |r| < 1 \), the series converges. To find the sum to infinity, we can use the formula \( S = \frac{a}{1 - r} \), where \( a \) is the first term and \( r \) is the common ratio. Here, \( a = 45 \) and \( r = \frac{1}{3} \). Plugging in these values gives us: \[ S = \frac{45}{1 - \frac{1}{3}} = \frac{45}{\frac{2}{3}} = 45 \times \frac{3}{2} = 67.5. \] Thus, the sum to infinity of the series is \( 67.5 \).