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Finding the Fourth Proportional to 439.58, 659.59 and 285.80

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Solution

The fourth proportional to 439.58, 659.59 and 285.80 is: 428.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    439.58 : 659.59 = 285.80 : x
  2. Step 2: Convert to fraction form
    439.58/659.59 = 285.80/x
  3. Step 3: Cross multiply
    439.58x = 659.59 × 285.80
  4. Step 4: Simplify right side
    439.58x = 188,513.98
  5. Step 5: Solve for x
    x = 188,513.98/439.58
  6. Step 6: Final answer
    x = 428.85

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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.