A. 300x8!
B. 900x8!
C. 600x8!
D. 90x8!
In how many ways can a collection of 30 books be divided into two groups of 10 and 20 so that the first group always contains a particular book?
An n-digit number is a positive number with exactly n digits. Nine hundred distinct n-digit numbers are to be formed using only three digits 2,5 and 7. The smallest value of n for which this is possible is
The sum of divisors of 253453 is
The number of ways in which 5 boys and 4 girls can sit in a row so that all the girls come together and 2 particular girls never be together is
1/n!+1/(n+1)!1/(n+2)! =
If (m+n)P2 = 90, (m-n)P2 = 30 then (m,n) =
20 passengers are to travel by a double decked bus which can accommodate 13 in the upper deck and 7 in the lower deck. The number of ways that they can be distributed is
If a,b,c are the number of 4 digited numbers that can be formed using the digits 2,4,5,7,8 that are divisible by 3,4,5 respectively then the ascending order of a,b,c is
Three persons A,B,C are to speak at a function along with 7 other persons.If the person speak in random order,the probability that A speaks before B and B speaks before C is
The number of ways in which the following prizes be given to a class of 20 boys, first and second in Mathematics, first and second in Physics, first in Chemistry and first in English is