Question

Just look at the picture.....​

Answer 1

The answer is S25=925

Answer 2

is equal to 925 i think cuz

Explanation:

summation of arithmetic sequence

n=1 , 3n-2=3-2=1 , a=1, d=3.

sn=n+3n(n-1)

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2

a=1 ,d=3 sn= n+3n(n-1)

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2

S25=25+3×25(25-1)

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2

25+900=925

so the answer will be 925