From the set `{2, 3, 4, 5, 6, 7, 8, 9}`, how many pairs of co-primes can be formed?

From the digits 2, 3, 4, 5, 6 and 7, how many 5-digit numbers can be formed that have distinct digits and are multiples of 12?

Mr. A randomly picks 3 distinct numbers from the set {1, 2, 3, 4, 5, 6, 7, 8, 9} and arranges them in descending order to form a three digit number. Mr. B randomly picks 3 distinct numbers from the set {1, 2, 3, 4, 5, 6, 7, 8} and also arranges them in descending order to form a 3 digit number. Q. The probability that A and B has the same 3 digit number is :

From the digits 1,2,3,4,5,6 how many three - digit odd numbers can be formed when the repetition of the digits is not allowed?

If a digit is chosen at random from the digits 1,\ 2,\ 3,\ 4,\ 5,\ 6,\ 7,\ 8,\ 9 , then the probability that the digit is even, is (a) 4/9 (b) 5/9 (c) 1/9 (d) 2/3

How many different numbers of six digits each can be formed from the digits 4, 5, 6, 7, 8, 9 when repetition of digits is not allowed?

How many different numbers of six digits each can be formed from the digits 4, 5, 6, 7, 8, 9 when repetition of digits is not allowed?

Of all the mappings that can be defined from the set A :{1,2,3,4} to B : {5,6,7,8,9} , a mapping is randomly selected. The chance that the selected mapping is strictly monotonic is

If a digit is chosen at random from the digits 1,\ 2,\ 3,\ 4,\ 5,\ 6,\ 7,\ 8,\ 9 , then the probability that it is odd, is (a) 4/9 (b) 5/9 (c) 1/9 (d) 2/3

Five different digits from the setoff numbers {1,2,3,4,5,6,7} are written in random order. How many numbers can be formed using 5 different digits from set {1,2,3,4,5,6,7} if the number is divisible by 9?

How many numbers between 5000 and 10,000 can be formed using the digits 1,2,3,4,5,6,7,8,9, each digit appearing not more than once in each number?