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Finding the Fourth Proportional to 388.47, 582.06 and 285.79

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Solution

The fourth proportional to 388.47, 582.06 and 285.79 is: 428.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.47 : 582.06 = 285.79 : x
  2. Step 2: Convert to fraction form
    388.47/582.06 = 285.79/x
  3. Step 3: Cross multiply
    388.47x = 582.06 × 285.79
  4. Step 4: Simplify right side
    388.47x = 166,346.93
  5. Step 5: Solve for x
    x = 166,346.93/388.47
  6. Step 6: Final answer
    x = 428.21

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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.