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Finding the Fourth Proportional to 415.35, 623.21 and 285.39

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Solution

The fourth proportional to 415.35, 623.21 and 285.39 is: 428.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    415.35 : 623.21 = 285.39 : x
  2. Step 2: Convert to fraction form
    415.35/623.21 = 285.39/x
  3. Step 3: Cross multiply
    415.35x = 623.21 × 285.39
  4. Step 4: Simplify right side
    415.35x = 177,856.47
  5. Step 5: Solve for x
    x = 177,856.47/415.35
  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.