If three numbers are in the ratio 3 : 2 : 5 such that the sum of their squares…

2024

If three numbers are in the ratio 3 : 2 : 5 such that the sum of their squares is equal to 1862, the middle number is equal to :

  1. A.

    7

  2. B.

    14

  3. C.

    21

  4. D.

    35

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Correct answer: B

Let the three numbers be 3x, 2x, and 5x, as they are in the ratio 3 : 2 : 5.

Sum of their squares: (3x)² + (2x)² + (5x)² = 9x² + 4x² + 25x² = 38x².

Given that the sum of squares is 1862, so 38x² = 1862.

Solving for x: x² = 1862 / 38 = 49, so x = 7.

The middle number is 2x = 2 × 7 = 14.

हिन्दी उत्तर: माना तीन संख्याएँ 3x, 2x और 5x हैं, क्योंकि वे 3 : 2 : 5 के अनुपात में हैं।

उनके वर्गों का योग: (3x)² + (2x)² + (5x)² = 9x² + 4x² + 25x² = 38x²।

दिया गया है कि वर्गों का योग 1862 है, इसलिए 38x² = 1862।

x के लिए हल करने पर: x² = 1862 / 38 = 49, इसलिए x = 7।

मध्य वाली संख्या 2x = 2 × 7 = 14 है।

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