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If ""^(12)C(5) =^(12)C(r)then r=...

 If `""^(12)C_(5) =^(12)C_(r)````then r=_____

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The correct Answer is:
5 or 7
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If ""^(12)C_(5) + ^(12)C_(6) = ^(x)C_(6) then x = _________

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Knowledge Check

  • IF ""^15 C_r: "^15 C_(r-1)=11:5 then r=

    A
    4
    B
    5
    C
    6
    D
    7

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    If .^(18)C_(r) = .^(18)C_(r+1) , then evaluate .^(r)C_(5) .

    If .^(16)C_(r) = .^(16)C_(r+6) , then find .^(5)C_(r) .

    (i) If .^(n)C_(18)=.^(n)C_(12) then find the value of .^(32)C_(n) . (ii) If .^(10)C_(r)=.^(10)C_(r+4) then find the value of .^(5)C_(r) .

    (i) Prove that: ""^(n)P_(r) = ""^(n-1)P_(r) + r. ""^(n-1)P_(r–1) (ii) If ""^(20)C_(r+2) = ""^(20)C_(2r–3) find ""^(12)C_(r) (iii) Find the ratio ""^(20)C_(p) "to" ""^(25)C_(r) when each of them has the greatest value possible. (iv) Prove that ""(n-1)C_(3) + ""^(n-1)C_(4) gt ""^(n)C_(3) if n> 7 (v) Find r if ""^(15)C_(3r) = ""^(15)C_(r+3 )

    Find r if ""^(15) C_(r+1) = ""^(15) C_(3r-5) .

    If .^(15)C_(r): .^(15)C_(r-1) = 1:5 , then find r.

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