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Finding the Fourth Proportional to 389.20, 583.77 and 129.18

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Solution

The fourth proportional to 389.20, 583.77 and 129.18 is: 193.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.20 : 583.77 = 129.18 : x
  2. Step 2: Convert to fraction form
    389.20/583.77 = 129.18/x
  3. Step 3: Cross multiply
    389.20x = 583.77 × 129.18
  4. Step 4: Simplify right side
    389.20x = 75,411.41
  5. Step 5: Solve for x
    x = 75,411.41/389.20
  6. Step 6: Final answer
    x = 193.76

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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.