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Finding the Fourth Proportional to 508.78, 702.07 and 287.69

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Solution

The fourth proportional to 508.78, 702.07 and 287.69 is: 396.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    508.78 : 702.07 = 287.69 : x
  2. Step 2: Convert to fraction form
    508.78/702.07 = 287.69/x
  3. Step 3: Cross multiply
    508.78x = 702.07 × 287.69
  4. Step 4: Simplify right side
    508.78x = 201,978.52
  5. Step 5: Solve for x
    x = 201,978.52/508.78
  6. Step 6: Final answer
    x = 396.98

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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.