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If ^(56)P(r+6):^(54)P(r+3)=30800 :1, fi...

If ` ^(56)P_(r+6):^(54)P_(r+3)=30800 :1,` find `r`.

A

40

B

41

C

42

D

None of these

Text Solution

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The correct Answer is:
B
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