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Finding the Fourth Proportional to 689.78, 951.82 and 395.06

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Solution

The fourth proportional to 689.78, 951.82 and 395.06 is: 545.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.78 : 951.82 = 395.06 : x
  2. Step 2: Convert to fraction form
    689.78/951.82 = 395.06/x
  3. Step 3: Cross multiply
    689.78x = 951.82 × 395.06
  4. Step 4: Simplify right side
    689.78x = 376,020.26
  5. Step 5: Solve for x
    x = 376,020.26/689.78
  6. Step 6: Final answer
    x = 545.13

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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.