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Finding the Fourth Proportional to 385.29, 531.15 and 286.87

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Solution

The fourth proportional to 385.29, 531.15 and 286.87 is: 395.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.29 : 531.15 = 286.87 : x
  2. Step 2: Convert to fraction form
    385.29/531.15 = 286.87/x
  3. Step 3: Cross multiply
    385.29x = 531.15 × 286.87
  4. Step 4: Simplify right side
    385.29x = 152,371.00
  5. Step 5: Solve for x
    x = 152,371.00/385.29
  6. Step 6: Final answer
    x = 395.47

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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.