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Finding the Fourth Proportional to 385.81, 532.31 and 287.60

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Solution

The fourth proportional to 385.81, 532.31 and 287.60 is: 396.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.81 : 532.31 = 287.60 : x
  2. Step 2: Convert to fraction form
    385.81/532.31 = 287.60/x
  3. Step 3: Cross multiply
    385.81x = 532.31 × 287.60
  4. Step 4: Simplify right side
    385.81x = 153,088.26
  5. Step 5: Solve for x
    x = 153,088.26/385.81
  6. Step 6: Final answer
    x = 396.80

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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.