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When a particular number is subtracted from each of 7, 9, 11 and 15, the resulting numbers are in proportion. The number to be subtracted is -

11
22
33
45

Answer:- 1

Explanation:-

Solution:

Let the required number be x
Then,

= \frac{7 - x}{9 - x} = \frac{11 - x}{15 - x}

$= \frac{{7 - x}}{{9 - x}} = \frac{{11 - x}}{{15 - x}}$ ⇒ (7 - x)(15 - x) = (11 - x)(9 - x)
⇒ 105 - 22x + x² = 99 - 20x + x²
⇒ 2x = 6
⇒ x = 3

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⇒ (7 - x)(15 - x) = (11 - x)(9 - x)
⇒ 105 - 22x + x² = 99 - 20x + x²
⇒ 2x = 6
⇒ x = 3 ", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "

Solution:

Let the required number be x
Then,

= \frac{7 - x}{9 - x} = \frac{11 - x}{15 - x}

$= \frac{{7 - x}}{{9 - x}} = \frac{{11 - x}}{{15 - x}}$ ⇒ (7 - x)(15 - x) = (11 - x)(9 - x)
⇒ 105 - 22x + x² = 99 - 20x + x²
⇒ 2x = 6
⇒ x = 3 ", "dateCreated": "7/24/2019 10:09:12 AM" } }

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