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Find the sum of the first 49 terms of the arithmetic series. 36+42+48 +54 + ... S49 =

User John Fish
by
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1 Answer

5 votes

Answer:

S₄₉ = 8820

Explanation:

the sum to n terms of an arithmetic series is


S_(n) =
(n)/(2) [ 2a₁ + (n - 1)d ]

where a₁ is the first term and d the common difference

here a₁ = 36 and d = a₂ - a₁ = 42 - 36 = 6 , then

S₄₉ =
(49)/(2) [ (2 × 36) + (48 × 6) ]

= 24.5 (72 + 288)

= 24.5 × 360

= 8820

User Rel
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