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Finding the Fourth Proportional to 490.66, 735.28 and 420.86

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Solution

The fourth proportional to 490.66, 735.28 and 420.86 is: 630.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.66 : 735.28 = 420.86 : x
  2. Step 2: Convert to fraction form
    490.66/735.28 = 420.86/x
  3. Step 3: Cross multiply
    490.66x = 735.28 × 420.86
  4. Step 4: Simplify right side
    490.66x = 309,450.73
  5. Step 5: Solve for x
    x = 309,450.73/490.66
  6. Step 6: Final answer
    x = 630.69

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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.