The product of the digits of a two digit positive number is 24. If 18 is added to the number then the digits of the number are interchanged. Find the number.
Asked by Topperlearning User | 26 Jul, 2017, 12:56: PM
Let the digit at ten's place = x
Then, digit at one's place =
Original number = 10x +
On interchanging the digits, new number = + x
According to the question,
10x + + 18 = + x
10x2 + 24 + 18x = 240 + x2
9x2 + 18x - 216 = 0
x2 + 2x - 24 = 0
(x + 6) (x - 4) = 0
x = -6 or 4
But x can't be negative, so, x = 4
Digit at ten's place = x = 4 and digit at one's place == 6
Thus, the original number is 46.
Answered by | 26 Jul, 2017, 02:56: PM