Question 1104001
The common difference is 4, the difference between each term.
The tenth term is 
a10=a1+(n-1)d
=3+9(4)=39
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Sum is (n/2)(a1+a10)=5(3+39)=5(42)=210; the 5 comes from n/2 and n is 10 terms.
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series is 3,7,11,15,19,23,27,31,35,39
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