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Mathematics
Mathematics
Problem
Let
a
1
,
a
2
,
…
,
a
30
a_1, a_2, \dots, a_{30}
a
1
,
a
2
,
…
,
a
30
be an A.P.,
S
=
∑
i
=
1
30
a
i
S = \sum_{i=1}^{30} a_i
S
=
∑
i
=
1
30
a
i
and
T
=
∑
i
=
1
15
a
(
2
i
−
1
)
T = \sum_{i=1}^{15} a_{(2i-1)}
T
=
∑
i
=
1
15
a
(
2
i
−
1
)
. If
a
5
=
27
a_5 = 27
a
5
=
27
and
S
−
2
T
=
75
S - 2T = 75
S
−
2
T
=
75
, then
a
10
a_{10}
a
10
is equal to (a) 47 (b) 52 (c) 42 (d) 57
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