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Finding the Fourth Proportional to 805.72, 1,208.68 and 285.62

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Solution

The fourth proportional to 805.72, 1,208.68 and 285.62 is: 428.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.72 : 1,208.68 = 285.62 : x
  2. Step 2: Convert to fraction form
    805.72/1,208.68 = 285.62/x
  3. Step 3: Cross multiply
    805.72x = 1,208.68 × 285.62
  4. Step 4: Simplify right side
    805.72x = 345,223.18
  5. Step 5: Solve for x
    x = 345,223.18/805.72
  6. Step 6: Final answer
    x = 428.47

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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.