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What is the sum of the first 47 terms of the sequence? -215, -201, -187, -173, ...​

User Boqapt
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1 Answer

2 votes

Answer:

5029

Explanation:

There is a common difference between consecutive terms, that is

d = - 201 - (- 215) = - 187 - (- 201) = - 173 - (- 187) = 14

This indicates the sequence is arithmetic with sum to n term

= [ 2a₁ + (n - 1)d ]

where a₁ is the first term and d the common difference

Here a₁ = - 215 and d = 14 , then

= [ (2 × - 215) + (46 × 14) ]

= 23.5 (- 430 + 644)

= 23.5 × 214

= 5029

User Reukiodo
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4.6k points