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Finding the Fourth Proportional to 490.89, 736.20 and 285.42

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Solution

The fourth proportional to 490.89, 736.20 and 285.42 is: 428.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.89 : 736.20 = 285.42 : x
  2. Step 2: Convert to fraction form
    490.89/736.20 = 285.42/x
  3. Step 3: Cross multiply
    490.89x = 736.20 × 285.42
  4. Step 4: Simplify right side
    490.89x = 210,126.20
  5. Step 5: Solve for x
    x = 210,126.20/490.89
  6. Step 6: Final answer
    x = 428.05

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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.