Question:
In a two-digit number, the digit at the units place is double the digit in the tens place. The number exceeds the sum of its digits by 18. Find the number.
Solution:
Let the tens digit be x.
The digit in the units place is 2x.
Number = 10x + 2x
Given:
(x + 2x) + 18 = (10x + 2x)
∴ 3x + 18 = 12x
12x - 3x = 18
9x =18
$x=\frac{18}{2}=2$
The digit in the tens place is 2.
The digit in the units place is twice the digit in the tens place.
The digit in the units place is 4.
Therefore, the number is 24.
Click here to get exam-ready with eSaral
For making your preparation journey smoother of JEE, NEET and Class 8 to 10, grab our app now.