Science (English Medium) Class 11 - CBSE Question Bank Solutions

If ²⁰C_r = ²⁰C_r−10, then ¹⁸C_r is equal to

If ²⁰C_r = ²⁰C_{r + 4} , then ^rC₃ is equal to

If ¹⁵C_3r = ¹⁵C_{r + 3} , then r is equal to

If ²⁰C_{r + 1} = ²⁰C_{r − 1} , then r is equal to

If C (n, 12) = C (n, 8), then C (22, n) is equal to

If ^mC₁ = ⁿC₂ , then

If ⁿC₁₂ = ⁿC₈ , then n =

If ⁿC_r + ⁿC_{r + 1} = ^n + 1C_x , then x =

If\[\ ^{( a^2 - a)}{}{C}_2 = \ ^{( a^2 - a)}{}{C}_4\] , then a =

⁵C₁ + ⁵C₂ + ⁵C₃ + ⁵C₄ +⁵C₅ is equal to

Total number of words formed by 2 vowels and 3 consonants taken from 4 vowels and 5 consonants is equal to

There are 12 points in a plane. The number of the straight lines joining any two of them when 3 of them are collinear, is

Three persons enter a railway compartment. If there are 5 seats vacant, in how many ways can they take these seats?

In how many ways can a committee of 5 be made out of 6 men and 4 women containing at least one women?

There are 10 points in a plane and 4 of them are collinear. The number of straight lines joining any two of them is

There are 13 players of cricket, out of which 4 are bowlers. In how many ways a team of eleven be selected from them so as to include at least two bowlers?

If C₀ + C₁ + C₂ + ... + C_n = 256, then ²ⁿC₂ is equal to

The number of ways in which a host lady can invite for a party of 8 out of 12 people of whom two do not want to attend the party together is