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Finding the Fourth Proportional to 388.06, 581.21 and 285.09

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Solution

The fourth proportional to 388.06, 581.21 and 285.09 is: 426.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.06 : 581.21 = 285.09 : x
  2. Step 2: Convert to fraction form
    388.06/581.21 = 285.09/x
  3. Step 3: Cross multiply
    388.06x = 581.21 × 285.09
  4. Step 4: Simplify right side
    388.06x = 165,694.62
  5. Step 5: Solve for x
    x = 165,694.62/388.06
  6. Step 6: Final answer
    x = 426.98

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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.