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Value of a11 and s11

Value of a11 and s11-example-1

1 Answer

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Answer and Step-by-step explanation:

The formula for an arithmetic sequence is:


a_(n) = a_(1) + (n-1)d

Plug in the given values.


a_(11) = 2.5 + (11 -1)(1.5)\\\\a_(11)=2.5 + (10)(1.5)\\\\a_(11) = 2.5 + 15\\\\a_(11)=4

The formula for the sum on an arithmetic sequence is:


S_(n) = (n(a_1+a_n))/(2)

Plug in the values.


S_(11) = (11(2.5 + 4))/(2) = 35.75

#teamtrees #PAW (Plant And Water)

I hope this helps!

User Husain Basrawala
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