Question

the sum of digits of a 2 digit number is 7 if the digits are reversed the new number decrease by 2equals twice the original number

Answer 1

Let x be tens digit and y be once digit
Case 1

X+y=7

Case2
19x-8y=56
Solving this
Number=10*x+y
X=2,y=5
Number is 10*2+5 =25