Answer:
is equal to 925 i think cuz
Step-by-step 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
