The product of digits of a two digit number is 30.When 9 is subtracted from the number, the digits interchange the places.Find the number.

Explanation

Let first digit of number is `x` and second digit is `y`.

Then, the number will be `10x+y`.

Here, we are given,

`xy = 30->(1)`

Also, when we interchange the digits, number becomes, `10y+x`.

Also, we are given,

`10x+y-9 = 10y+x`

`=>9x=9y +9`

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