When we multiply a certain two digit number by the

When we multiply a certain two digit number by the sum of its digits 405 is achieved. If we multiply the number written in reverse order of the same digits by the sum of the digits,we get 486.Find the number?

Quiz

Answer/Solution

45

Steps/Work

Let the number be x y.
When we multiply the number by the sum of its digit
405 is achieved.
(10x+y)(x+y)=405....................1
If we multiply the number written in reverse order by its
sum of digits we get 486.
(10y+x)(x+y)=486......................2
dividing 1 and 2
(10x+y)(x+y)/(10y+x)(x+y) = 405/486.
10x+y / 10y+x = 5/6.
60x+6y = 50y+5x
55x=44y
5x = 4y.
From the above condition we conclude that the above
condition is satisfied by the second option i e b. 45.
ANSWER : B 45