Question

five times the sum of the digit of a of a two number is 9 less than the number formed by reversing it's digit. if four times the value of the digit at ones place is equal to half of the place value of the digit at ten place , find the number.​

Answer 1

Let the unit digit be y and tens digit be x

Number is 10x+y

5(x+y) = (10y + x )-9

5x + 5y = 10y + x - 9

4y = (1/2)*10x

4y = 5x

y = 5x/4

5x + 5y = 10y + x - 9

5x - x = 10y - 5y - 9

4x = 5y - 9

4x = 5*(5x/4) - 9

4x = (25x - 36)/4

16x = 25x - 36

25x - 16x = 36

9x = 36

x = 4

So,

y = 5*4/4= 5

Number = 10x + y = 10*4 + 5 = 40+5= 45