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Finding the Fourth Proportional to 385.56, 531.68 and 280.44

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Solution

The fourth proportional to 385.56, 531.68 and 280.44 is: 386.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.56 : 531.68 = 280.44 : x
  2. Step 2: Convert to fraction form
    385.56/531.68 = 280.44/x
  3. Step 3: Cross multiply
    385.56x = 531.68 × 280.44
  4. Step 4: Simplify right side
    385.56x = 149,102.94
  5. Step 5: Solve for x
    x = 149,102.94/385.56
  6. Step 6: Final answer
    x = 386.72

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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.