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The digits of a positive integer, having three digits are in A. P and their sum is 15.The number obtained by reversing the digits is 594 less than the original number. Find the number |
Answer» AnswEr:-Three digits number = 852Let the three digits of the number be a, a + d & a + 2d as they are in A.P ∴ Number = a + 10(a + d) + 100(a + 2d) Case 1:- ⇒ a + (a + d) + (a + 2d) = 15 ⇒ a + a + d + a + 2d = 15 ⇒ 3a + 3D = 15 ⇒ 3(a + d) = 15 ⇒ a + d = 15/3 ⇒ a + d = 5 [Eq.1] Case 2:- Number obtained by REVERSING digits:- ∴ Number = 100a + 10(a + d) + (a + 2d) According to question:- ⇒ [a + 10(a + d) + 100(a + 2d)] - [100a + 10(a + d) + (a + 2d)] = 594 ⇒ a + 10a + 10d + 100a + 200d - 100a - 10a - 10d - a - 2d = 594 ⇒ 111a + 210d - 111a - 12D = 594 ⇒ 198d = 594 ⇒ d = 594/198 ⇒ d = 3 Put this value in (Eq.1) ⇒ a + 3 = 5 ⇒ a = 5 - 3 ⇒ a = 2 ⋆ THREE DIGITS OF THE NUMBER:- ↠ First DIGIT = a = 2 ↠ Second digit = a + d = 2 + 3 = 5 ↠Third digit = a + 2d = 2 + 2(3)= 2 + 6 = 8 ⋆ THREE DIGITS NUMBER :- ⇒ Number = 2 + 10(2 + 3) + 100{2 + 2(3)} ⇒ Number = 2 + 10(5) + 100(8) ⇒ Number = 2 + 50 + 800 ⇒ Number = 852 Therefore, Three digits number = 852 . |
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