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Finding the Fourth Proportional to 487.39, 729.81 and 389.44

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Solution

The fourth proportional to 487.39, 729.81 and 389.44 is: 583.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.39 : 729.81 = 389.44 : x
  2. Step 2: Convert to fraction form
    487.39/729.81 = 389.44/x
  3. Step 3: Cross multiply
    487.39x = 729.81 × 389.44
  4. Step 4: Simplify right side
    487.39x = 284,217.21
  5. Step 5: Solve for x
    x = 284,217.21/487.39
  6. Step 6: Final answer
    x = 583.14

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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.