MEDIUM
Earn 100

How many numbers between 3000 and 5000 divisible by 5 can be made using the digits 0, 4, 3. 2. 5?

Important Questions on Permutation and Combination

HARD
An urn contains 5 red marbles, 4 black marbles and 3 white marbles. Then, the number of ways in which 4 marbles can be drawn so that at the most three of them are red is ___________.
MEDIUM
Let S=a,b :a, bZ, 0a, b18. The number of elements x,y in S such that 3x+4y+5 is divisible by 19 is,
MEDIUM
If the four letter words (need not be meaningful) are to be formed using the letters from the word "MEDITERRANEAN" such that the first letter is R and the fourth letter is E, then the total number of all such words is :
MEDIUM
n-digit numbers are formed using only three digits 2, 5 and 7. The smallest value of n for which 900 such distinct numbers can be formed is :
MEDIUM
The number of numbers between 2,000 and 5,000 that can be formed with the digits 0, 1, 2, 3, 4 (repetition of digits is not allowed) and are multiple of 3 is
EASY
If the number of five digit numbers with distinct digits and 2 at the 10th place is 336k , then k is equal to:
HARD
Let S=a, ba, bZ,0a, b18 . The number of lines in R2 passing through 0,0 and exactly one other point in S is-
MEDIUM
A five-digit number divisible by 3 is to be formed using the numbers 0,1,2,3,4 and 5 without repetition. The total number of ways this can be done is
MEDIUM
Ten points lie in a plane so that no three of them are collinear. The number of lines passing through exactly two of these points and dividing the plane into two regions each containing four of the remaining points is
EASY
If S is a set with 10 elements and A=x, y:x, yS, xy , then the number of elements in A is
MEDIUM
Five points are marked on a circle. The number of distinct polygons of three or more sides can be drawn using some (or all) of the five points as vertices is
MEDIUM
The number of natural numbers less than 7000 which can be formed by using the digits 0, 1, 3, 7, 9 (repetition of digits allowed) is equal to:
EASY
Let S={0,1,2,3,,100}. The number of ways of selecting x, yS such that xy and x+y=100 is
EASY
Let M=a1,a2,a3:ai1,2,3,4,a1+a2+a3=6. Then the number of elements in M is
MEDIUM
Let m (respectively, n ) be the number of 5 -digit integers obtained by using the digits 1,2,3,4,5 with repetitions (respectively, without repetitions) such that the sum of any two adjacent digits is odd. Then mn is equal to
MEDIUM
The chairs at an auditorium are to be labelled with a letter and a positive integer not exceeding 100. The largest number of chairs that can be marked differently is equal to
MEDIUM
The number of ways of dividing 15  men and 15 women into 15 couples, each consisting of man and woman is
MEDIUM
The number of integers n with 100n999 and containing at most two distinct digits is
MEDIUM
The number of 5 digit numbers which are divisible by 4, with digits from the set {1,2,3,4,5} and the repetition of digits is allowed, is _____.
MEDIUM
The number of integers greater than 6000 that can be formed, using the digits 3, 5, 6, 7 and 8, without repetition is