Find the fourth proportional to 1.5, 4.5 and 3.5

Sum

Let the fourth proportional to 1.5, 4.5 and 3.5 be x.

`\implies` 1.5 : 4.5 = 3.5 : x

`\implies` 1.5 × x = 3.5 × 4.5

`\implies` x = 10.5

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Chapter 7: Ratio and Proportion (Including Properties and Uses) - Exercise 7 (B) [Page 89]

Chapter 7 Ratio and Proportion (Including Properties and Uses)
Exercise 7 (B) | Q 2. (i) | Page 89

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