मराठी

The three scales below are perfectly balanced if • = 3. What are the values of ∆ and * ? a. b. c. - Mathematics

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प्रश्न

The three scales below are perfectly balanced if • = 3. What are the values of ∆ and * ?

a.
b.
c.
संख्यात्मक
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उत्तर

Given that • = 3  ...(i)

  1. 5* = 2Δ + 2•  ...(ii)
  2. 2Δ = 2* + 2•  ...(iii)
  3. 3* + 3• = 3Δ  ...(iv)

Putting the value of (iii) in (ii), we get

5* = 2* + 2• + 2•

⇒ 5* – 2* = 4•

⇒ 3* = 4 × 3  ...[Using (i)]

⇒ * = `(4 xx 3)/3` = 4

Putting the value of * and • in (iv), we get

3 × 4 + 3 × 3 = 3Δ

⇒ 3Δ = 21

⇒ Δ = `21/3`

⇒ Δ = 7

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पाठ 4: Simple Equations - Exercise [पृष्ठ ११६]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 7
पाठ 4 Simple Equations
Exercise | Q 106. | पृष्ठ ११६

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

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