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Finding the Fourth Proportional to 385.31, 531.85 and 306.77

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Solution

The fourth proportional to 385.31, 531.85 and 306.77 is: 423.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.31 : 531.85 = 306.77 : x
  2. Step 2: Convert to fraction form
    385.31/531.85 = 306.77/x
  3. Step 3: Cross multiply
    385.31x = 531.85 × 306.77
  4. Step 4: Simplify right side
    385.31x = 163,152.20
  5. Step 5: Solve for x
    x = 163,152.20/385.31
  6. Step 6: Final answer
    x = 423.44

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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.