Let n be the largest integer that is the product of exactly 3 distinct prime numbers ` x,y and 10x+y `where `x and y `are digits. What is the sum of the digits of `n`

Let n be the largest integer that is the product of exactly 3 distinct prime numbers x, y and 10x + y where x and y are the digits. What is the sum of digits of n ?

The ratio of the sum of the reciprocal of x and y to the product of the reciprocal of x and y is 1 : 3. What is sum of the numbers x and y?

It is given that the 10-digit number 55y1725x00 is exactly divisible by 88. What is the value of (y - x) ?

The arithemetic mean and the geometric mean of two distinct 2 -digit numbers x and y are two integers one of which can be obtained by reserving the digits of the other (in base 10 representation).Then x+y equals

let S ={1,2,3,…,24}. Define a relation '~' on S as x ~y is the product of the digits in x is same as that of the digits of y. (Note that is x is a single digit number then the product of the digits in x will be considered to be x.) Then the number of equivalence classes for this equivlence relation is

{:("Column A","X is a 3-digit number and Y is a 4-digit number. All the digits of X are greater than 4, and all the digit of Y are less than 5" ,"Column B"),("The sum of the digits of X" , ,"The sum of the digits of Y"):}