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Finding the Fourth Proportional to 309.62, 462.20 and 287.10

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Solution

The fourth proportional to 309.62, 462.20 and 287.10 is: 428.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.62 : 462.20 = 287.10 : x
  2. Step 2: Convert to fraction form
    309.62/462.20 = 287.10/x
  3. Step 3: Cross multiply
    309.62x = 462.20 × 287.10
  4. Step 4: Simplify right side
    309.62x = 132,697.62
  5. Step 5: Solve for x
    x = 132,697.62/309.62
  6. Step 6: Final answer
    x = 428.58

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.