If $^{15}{C_{3r}}{ = ^{15}}{C_{r + 3}}$, then the value of $r$ is
If $^{15}{C_{3r}}{ = ^{15}}{C_{r + 3}}$, then the value of $r$ is
- [IIT 1967]
- A
$3$
- B
$4$
- C
$5$
- D
$8$
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