Question

in a two digit number the tens digit is 3 times the unit digit. when the number is decreased by 54 the digits are reversed. find the number

Answer 1

let the units digit be x
then the tens digit is 3x
so the number is 3x*10+x=31x
the no in reverse is x*10+3x=13x
so according to given condition
31x-54=13x
18x=54
x=54/18=3