Question and Answers Forum
Permutation and CombinationQuestion and Answers: Page 20
|
Question and Answers Forum |
|
Permutation and CombinationQuestion and Answers: Page 20 |
| If (n_P_r /n_C_r ) −1=5, find the value of r |
| Find number of 4−letter words which can be formed using the letters of the word ′ALLAHABAD′ such that: NO repetition of letter and word should start “either” from H “or” ends with D ? |
| Find the number of all such 7−digit no. which satisfy conditions: 1) divisible by 3 2) repetition allowed 3) zero is not used. |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| A square is divided into 9 identical smaller squares.Six identical balls are to be placed in these smaller squares such that each of the three rows gets at least one ball(one ball in one square only).In how many different ways can this be done? a)91 b)51 c)81 d)41 |
|
|
|
|
| An unfair coin with the probability of getting head in one toss = (1/5). If coin tosses n times, the probability of getting 2 heads is equal to the probability of getting 3 heads. Find n |
| how many odd numbers greater than 60000 can be made from the digits 5,6,7,8,9,0 if no number contains any digit more than once? |
|
|
| In the sequence of numbers 1, 2, 11, 22, 111, 222, ... the sum of the digits in 999th terms is ?? |
|
|
|
|
|
|
|
|
| if ^n C_5 = ^n C_(11) find ^(18) C_n |
| if three numbers are drawn at random successively without replacement from a set S={1,2,......10}then probability that the minimum of the choosen number is 3 or their maximum is 7 Answer=((11)/(40)) |
|
|
| the sum of the four digit even numbers that can be formed with digits 0 3 5 4 without repitation |
| A particle, of mass 5kg,moves in a straight line its displacement,x metres after t seconds is given by x = t^3 − 4t^2 +4t. Find the magnitude of the impulses exerted on the particle when t=2. |