If the sum of their first n terms is Sn / TN = 3N + 1 / 2N-1, then the ratio of the fifth term of these two numbers is?
Sn=n(A1+An)/2
Tn=n(B1+Bn)/2
Sn / TN = (a1 + an) / (B1 + BN) and then 2N-1
an/bn=S2n-1/T2n-1
Sn / TN = 3N + 1 / 2N-1, n generation 2N-1
S2n-1/T2n-1=6n-2/4n-3
a5/b5=28/17
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