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Mathematics
Problem
Consider the series represented by
S
=
∑
k
=
0
n
−
1
(
5
k
+
7
)
\displaystyle S=\sum_{k=0}^{n-1}(5k+7)
S
=
k
=
0
∑
n
−
1
(
5
k
+
7
)
. Which of the following gives the first term
a
a
a
and the common difference
d
d
d
of the corresponding arithmetic progression? a)
a
=
12
,
d
=
5
a=12,\; d=5
a
=
12
,
d
=
5
b)
a
=
7
,
d
=
5
a=7,\; d=5
a
=
7
,
d
=
5
c)
a
=
5
,
d
=
7
a=5,\; d=7
a
=
5
,
d
=
7
d)
a
=
7
,
d
=
12
a=7,\; d=12
a
=
7
,
d
=
12
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