Find the sum of the first 47 terms of the following series, to the nearest integer.
Answer Attempt 1 out of 2
12,16,20,...
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Answer :

To find the sum of the first 47 terms of the arithmetic series that starts with 12 and increases by 4 each time, we can use the formula for the sum of an arithmetic series, which is: \[ S_n = \frac{n}{2} \times (a_1 + a_n) \] where: - \( S_n \) is the sum of the first \( n \) terms of the series, - \( n \) is the number of terms, - \( a_1 \) is the first term, and - \( a_n \) is the \( n \)th term. Given in the problem: - The first term (\( a_1 \)) is 12, - The common difference (\( d \)) is 4, and - The number of terms (\( n \)) is 47. First, let's find the 47th term (\( a_{47} \)) of the series. We can use the formula for the \( n \)th term of an arithmetic series: \[ a_n = a_1 + (n - 1)d \] Substituting our known values: \[ a_{47} = 12 + (47 - 1) \times 4 \] \[ a_{47} = 12 + 46 \times 4 \] \[ a_{47} = 12 + 184 \] \[ a_{47} = 196 \] Now, we can find the sum of the first 47 terms (\( S_{47} \)): \[ S_{47} = \frac{47}{2} \times (12 + 196) \] \[ S_{47} = \frac{47}{2} \times 208 \] \[ S_{47} = 23.5 \times 208 \] \[ S_{47} = 4892 \] We don't need to round this answer to the nearest integer because it's already an integer. So, the sum of the first 47 terms of the series is 4892.