Q5 of 25 Page 79

In a two-digit number, a digit at the ten’s place is twice the digit at unit’s place. If the number obtained by interchanging the digits is added to the original number, the sum is 66. Find the number

let the number at digit place be

So, da igit at tens place is 2x.


Number is 10×2x + x = 21x


Now interchanging the digits, at digit place we have 2x and at tens place x.number is 10×x + 2x = 12x


According to the given condition’s 12x + 21x = 66


33x = 66


Dividing both side by 33


X = 2


Digit at tens place is 2 × 2 = 4


Number is 42


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