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Finding the Fourth Proportional to 865.10, 1,297.81 and 280.24

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Solution

The fourth proportional to 865.10, 1,297.81 and 280.24 is: 420.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    865.10 : 1,297.81 = 280.24 : x
  2. Step 2: Convert to fraction form
    865.10/1,297.81 = 280.24/x
  3. Step 3: Cross multiply
    865.10x = 1,297.81 × 280.24
  4. Step 4: Simplify right side
    865.10x = 363,702.22
  5. Step 5: Solve for x
    x = 363,702.22/865.10
  6. Step 6: Final answer
    x = 420.42

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.