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Finding the Fourth Proportional to 255.87, 384.55 and 212.81

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Solution

The fourth proportional to 255.87, 384.55 and 212.81 is: 319.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    255.87 : 384.55 = 212.81 : x
  2. Step 2: Convert to fraction form
    255.87/384.55 = 212.81/x
  3. Step 3: Cross multiply
    255.87x = 384.55 × 212.81
  4. Step 4: Simplify right side
    255.87x = 81,833.63
  5. Step 5: Solve for x
    x = 81,833.63/255.87
  6. Step 6: Final answer
    x = 319.83

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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.