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Finding the Fourth Proportional to 508.87, 702.16 and 287.78

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Solution

The fourth proportional to 508.87, 702.16 and 287.78 is: 397.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    508.87 : 702.16 = 287.78 : x
  2. Step 2: Convert to fraction form
    508.87/702.16 = 287.78/x
  3. Step 3: Cross multiply
    508.87x = 702.16 × 287.78
  4. Step 4: Simplify right side
    508.87x = 202,068.94
  5. Step 5: Solve for x
    x = 202,068.94/508.87
  6. Step 6: Final answer
    x = 397.09

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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.