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Mathematics
Problem
If
n
C
r
=
210
{}^{n}C_{r}=210
n
C
r
=
210
and
n
C
r
+
1
=
252
{}^{n}C_{r+1}=252
n
C
r
+
1
=
252
, find the ordered pair
(
n
,
r
)
(n, r)
(
n
,
r
)
. a)
(
10
,
6
)
(10,6)
(
10
,
6
)
b)
(
10
,
5
)
(10,5)
(
10
,
5
)
c)
(
10
,
4
)
(10,4)
(
10
,
4
)
d)
(
21
,
2
)
(21,2)
(
21
,
2
)
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