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Finding the Fourth Proportional to 655.20, 978.84 and 655.20

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Solution

The fourth proportional to 655.20, 978.84 and 655.20 is: 978.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    655.20 : 978.84 = 655.20 : x
  2. Step 2: Convert to fraction form
    655.20/978.84 = 655.20/x
  3. Step 3: Cross multiply
    655.20x = 978.84 × 655.20
  4. Step 4: Simplify right side
    655.20x = 641,335.97
  5. Step 5: Solve for x
    x = 641,335.97/655.20
  6. Step 6: Final answer
    x = 978.84

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.