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Mathematics
Problem
In an AP if
S
1
=
T
1
+
T
2
+
T
3
+
⋯
+
T
n
S_1 = T_1 + T_2 + T_3 + \dots + T_n
S
1
=
T
1
+
T
2
+
T
3
+
⋯
+
T
n
(
n
n
n
odd)
S
2
=
T
2
+
T
4
+
T
6
+
⋯
+
T
n
−
1
S_2 = T_2 + T_4 + T_6 + \dots + T_{n-1}
S
2
=
T
2
+
T
4
+
T
6
+
⋯
+
T
n
−
1
, then
S
1
/
S
2
=
S_1/S_2 =
S
1
/
S
2
=
(a)
2
n
n
−
1
\frac{2n}{n-1}
n
−
1
2
n
(b)
n
n
+
1
\frac{n}{n+1}
n
+
1
n
(c)
n
+
1
2
n
\frac{n+1}{2n}
2
n
n
+
1
(d)
n
+
1
n
\frac{n+1}{n}
n
n
+
1
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