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Hare, t1=131
t2=13+231+3
t3=13+23+331+3+5
So, tn=13+23+....+n31+3+5+....+(2n-1)=(n(n+1)2)2n2[1+2n-1]
=2n2(n+1)24n2
=(n+1)24
So we have to find the value of
n=19tn=n=19(n+1)24=14n=19(n2+2n+1)
=14{n=19n2+2n=19n+n=191}
=14[9(9+1)(29+1)6+29(9+1)2+91]
=14[90196+90+9]
=14[285+99]
=14384=96
Hence the correct option is (B).i.e 96
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