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Finding the Fourth Proportional to 489.38, 730.64 and 381.28

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Solution

The fourth proportional to 489.38, 730.64 and 381.28 is: 569.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.38 : 730.64 = 381.28 : x
  2. Step 2: Convert to fraction form
    489.38/730.64 = 381.28/x
  3. Step 3: Cross multiply
    489.38x = 730.64 × 381.28
  4. Step 4: Simplify right side
    489.38x = 278,578.42
  5. Step 5: Solve for x
    x = 278,578.42/489.38
  6. Step 6: Final answer
    x = 569.25

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.