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Finding the Fourth Proportional to 689.78, 951.89 and 395.04

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Solution

The fourth proportional to 689.78, 951.89 and 395.04 is: 545.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.78 : 951.89 = 395.04 : x
  2. Step 2: Convert to fraction form
    689.78/951.89 = 395.04/x
  3. Step 3: Cross multiply
    689.78x = 951.89 × 395.04
  4. Step 4: Simplify right side
    689.78x = 376,036.22
  5. Step 5: Solve for x
    x = 376,036.22/689.78
  6. Step 6: Final answer
    x = 545.15

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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.