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Mathematics
Problem
If
4
C
4
+
∑
r
=
1
5
5
C
r
{}^4C_4 + \sum_{r=1}^{5} {}^5C_r
4
C
4
+
∑
r
=
1
5
5
C
r
is equal to a.
4
C
3
{}^4C_3
4
C
3
b.
5
C
3
{}^5C_3
5
C
3
c.
5
C
4
{}^5C_4
5
C
4
d. None of these
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