A number consists of two digits such that the digit in the ten's place is less by 2 than the digit in the unit's place. Three times the number added to 6/7 times the number obtained by reversing the digits 108. The sum of the digits in the number is -

Question: A number consists of two digits such that the digit in the ten's place is less by 2 than the digit in the unit's place. Three times the number added to 6/7 times the number obtained by reversing the digits 108. The sum of the digits in the number is -

Solution:
ধরি,
একক স্থানীয় অঙ্কটি x এবং দশক স্থানীয় অঙ্কটি (x - 2)

সংখ্যাটি = 10((x - 2) + x
= 11x - 20

স্থান বিনিময়কৃত সংখ্যাটি = 10x + x - 2
= 11x - 2

ATQ,
3(11x - 20) + (6/7) (11x - 2) = 108
⇒ 33x - 60 + (6/7) (11x - 2) = 108
⇒ 231x - 420 + 66x - 12 = 756
⇒ 297x = 756 + 432
⇒ 297x = 1188
⇒ x = 1188/297
∴ x = 4


∴ অঙ্কগুলোর সমষ্টি = x + x - 2
= 2x - 2
= (2 × 4) - 2
= 6