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Finding the Fourth Proportional to 385.31, 578.12 and 255.48

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Solution

The fourth proportional to 385.31, 578.12 and 255.48 is: 383.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.31 : 578.12 = 255.48 : x
  2. Step 2: Convert to fraction form
    385.31/578.12 = 255.48/x
  3. Step 3: Cross multiply
    385.31x = 578.12 × 255.48
  4. Step 4: Simplify right side
    385.31x = 147,696.82
  5. Step 5: Solve for x
    x = 147,696.82/385.31
  6. Step 6: Final answer
    x = 383.32

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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.