Question

The sum of the factors of 9! Which are odd and are of the form 3m + 2, where m is a natural number is 

Solution

Correct option is

40

   

Odd factors of the form 3m + 2 are neither multiple of 2 nor multiples of 3. So the factors may be 1, 5, 7, 35 of which just 5 and 35 are of the form 3m + 2. Their sum is 40.

SIMILAR QUESTIONS

Q1

Let E = {1, 2, 3, 4} and F = {ab}. then the number of onto functions from E to F is

Q2

The number of ways of arranging letters of the word HAVANA so that V and N do not appear together is

Q3

The range of function 

Q4

The number of ways of arranging letters of the word RACHIT so that the vowels are in alphabetical order is

Q5

A five digit number divisible by 3 is to be formed using the numerals 0, 1, 2, 3, 4 and 5 without repetition. The total number of ways in which this can be done is

Q6

The number of ways in which a mixed double game can be arranged from amongst 9 married couple if no husband and wife play in the same game is 

Q7

The number of times the digit 3 will be written when listing the integers from 1 to 1000 is

Q8

The number of positive integers n such that 2n divides n! is

Q9

A class contains 4 boys and g girls. Every Sunday five students, including at least three boys go for a picnic to Appu Ghar, a different group being sent every week. During, the picnic, the class teacher gives each girl in the group a doll. If the total number of dolls distributed was 85, then value of g is    

Q10

Sum of all three digit numbers (no digit being zero) having the property that all digit are perfect squares, is