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Finding the Fourth Proportional to 385.44, 531.41 and 280.55

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Solution

The fourth proportional to 385.44, 531.41 and 280.55 is: 386.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.44 : 531.41 = 280.55 : x
  2. Step 2: Convert to fraction form
    385.44/531.41 = 280.55/x
  3. Step 3: Cross multiply
    385.44x = 531.41 × 280.55
  4. Step 4: Simplify right side
    385.44x = 149,083.02
  5. Step 5: Solve for x
    x = 149,083.02/385.44
  6. Step 6: Final answer
    x = 386.79

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.