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A number consists of two digits whose sum is 8. If 18 is added to the number its digits get interchanged. The number is?a) 53b) 35c) 92d) 63

Aniket Singh , 1 Year ago
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anser 1 Answers
Askiitians Tutor Team

Let's assume the number consists of two digits. Let the tens digit be represented as x and the ones digit as y.

So, the number can be written as: Number = 10x + y

Given:

The sum of the digits is 8. This means: x + y = 8

If 18 is added to the number, the digits get interchanged. This gives us the equation: (10x + y) + 18 = 10y + x

Now, let's solve the system of equations step by step.

Step 1: Simplify the second equation.
(10x + y) + 18 = 10y + x
This simplifies to:
10x + y + 18 = 10y + x
Now, move all terms involving x and y to one side:
10x - x = 10y - y - 18
9x = 9y - 18
Divide both sides by 9:
x = y - 2

Step 2: Substitute into the first equation.
We know x + y = 8. Substitute x = y - 2 into this equation:
(y - 2) + y = 8
2y - 2 = 8
2y = 10
y = 5

Step 3: Find x.
Now that we know y = 5, substitute this value into the equation x = y - 2:
x = 5 - 2
x = 3

Step 4: Construct the number.
The tens digit is 3 and the ones digit is 5. So, the number is 35.

Thus, the number is 35.

Answer: b) 35

Last Activity: 1 Year ago
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