A. 101

B. 50

C. 51

D. 204

The coefficients of three consecutive terms in the expansion of (1+x)^{n} are in the ratio 1:7:42, then n=

Which term of (2x-3y)^{12} when x=1, y=5/2 numerically greatest?

If two consecutive terms in the expansion of (x+a)^{n }are equal where n is a positive integer then (n+1)a/x+a is

If the sum of odd terms and the sum of even terms in the expansion of (x+a)^{n} are p and q respectively then p^{2}+q^{2}=

If the coefficients of (2r+1)^{th} term and (4r+5)^{th} term in the expansion of (1+x)^{10} are equal then r=