If C1518+2(C1618)+C1617+1=C3n, then n is equal to
19
20
8
24
21
Explanation for the correct option:
Find the value of n:
Given, C1518+2(C1618)+C1617+1=C3n
⇒ C1518+2(C1618)+C1617+C1717=C3n ; ∵Crn+Cr-1n=Crn+1
⇒ C1518+2(C1618)+C1718=C3n
⇒C1518+C1618+C1618+C1718=C3n
⇒ C1619+C1719=C3n
⇒ C1720=C3n
∴n=20
Hence, Option ‘B’ is Correct.
Determine n if
(i) (ii)