How many of them have exactly one of their digits as 7 ?

How many numbers are there between 100 and 1000 such that at least one of their digits is 7 ?

How many of them are divisible by 10 if 6 digit numbers formed by 0,1,3,5,7,9 when no digit repeated?

How many natural numbers from 1 to 1000 have none of their digits repeated ?

Show that there are 4536 numbers between 1000 and 10000, which have none of their digits repeated. Of these, how many are odd numbers ?

Write the advantages of recombinant therapeutics. How many of them have been approved world over for human use and how many are avaible in Indian market?

A and B are two candidates seeking admission in a college. The probability that A is selected is 0.7 and the probability that exactly one of them is selected is 0.6. find the chance that B is selected if the admission of one candidate is independent of the other.

In a certain city, all telephone numbers have six digits, the first two digits always being 41 or 42 or 46 or 62 or 64. How many telephone numbers have all six digits distinct ?

How many 4 digits numbers can be formed from the digits 1 to 9 if not digit can be repeated.

How many numbers can be formed from the digits 1, 2, 3, 9 if repetition of digits is not allowed ?

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 ?