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The difference between two positive numbers is 3. If the sum of their squares is 369, then sum of the numbers is :दो धनात्मक संख्याओं का अन्तर 3 है, यदि उनके वर्गों का योग 369 हो, तो उन संख्याओं का योग है :

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Correct answer: B. 27

Explanation

Let the numbers be x and y with x - y = 3 and x² + y² = 369. Then (x - y)² = 9 = 369 - 2xy, so 2xy = 360. Now (x + y)² = x² + y² + 2xy = 369 + 360 = 729, so x + y = 27 (numbers are 15 and 12). Hence the answer is 27.मान लें संख्याएँ x और y हैं, जहाँ x - y = 3 और x² + y² = 369। तब (x - y)² = 9 = 369 - 2xy, अतः 2xy = 360। अब (x + y)² = x² + y² + 2xy = 369 + 360 = 729, इसलिए x + y = 27 (संख्याएँ 15 और 12 हैं)। अतः उत्तर 27 है।

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