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2 years ago

Can someone please help me with this?

Mathematics

1 answer:

dsp732 years ago

3 0

Answer:

$S_{13}$ = 403

Step-by-step explanation:

the sum to n terms of an arithmetic series is

$S_{n}$ = $\frac{n}{2}$ (a + l) ← a is the first term and l the last term

here a = - 5 and l = 67 , then

$S_{13}$ = $\frac{13}{2}$ (- 5 + 67) = 6.5 × 62 = 403

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