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Finding the Fourth Proportional to 387.09, 580.65 and 140.31

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Solution

The fourth proportional to 387.09, 580.65 and 140.31 is: 210.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.09 : 580.65 = 140.31 : x
  2. Step 2: Convert to fraction form
    387.09/580.65 = 140.31/x
  3. Step 3: Cross multiply
    387.09x = 580.65 × 140.31
  4. Step 4: Simplify right side
    387.09x = 81,471.00
  5. Step 5: Solve for x
    x = 81,471.00/387.09
  6. Step 6: Final answer
    x = 210.47

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.