The sum of digits of a 2-digit number is 12. When the digits are reversed, the number becomes greater by eighteen. What is the difference between the digits in the number?  

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Answer (Detailed Solution Below)

Option 2 : 2
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Detailed Solution

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Calculation:

Let's assume that the 2-digit number is represented as 10x + y,

where x and y are the tens and units digits respectively.

We are given that the sum of the digits is 12, so we can write:

x + y = 12

Digits are reversed, the new number is represented as 10y + x.

According to the question

10y + x = 10x + y + 18

Simplifying this equation, we get:

9y - 9x = 18

Dividing both sides by 9, we get:

y - x = 2

∴ The difference between the digits in the number is 2.

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