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Finding the Fourth Proportional to 689.57, 951.91 and 409.89

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Solution

The fourth proportional to 689.57, 951.91 and 409.89 is: 565.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.57 : 951.91 = 409.89 : x
  2. Step 2: Convert to fraction form
    689.57/951.91 = 409.89/x
  3. Step 3: Cross multiply
    689.57x = 951.91 × 409.89
  4. Step 4: Simplify right side
    689.57x = 390,176.85
  5. Step 5: Solve for x
    x = 390,176.85/689.57
  6. Step 6: Final answer
    x = 565.83

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.