Number System
The difference between a two-digit number and the number obtained by interchanging its two digits is 45. The sum of the digit of the number is 9. What is the product of the two digits of the number?
Let the number be 10x + y.Therefore, x + y = 9 ..................(i)10x + y - (10y + x) = 4510x + y - 10y - x = 45Therefore, x - y = 5 ..................(ii)From (i) and (ii), x = 7, y = 2Number = 72Therefore, = x x y = 7 x 2 = 14
Let the digits be x and yTherefore, x + y = 12 .............(1)(10y + x) - (10x + y) Therefore, y - x = 4............. (2)Solving (1) and (2), y = 8 Therefore, x = 4There are two possible numbers 48 and 84. So the lowest no. is 48.
EXAMIANS