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Finding the Fourth Proportional to 259.61, 389.31 and 129.50

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Solution

The fourth proportional to 259.61, 389.31 and 129.50 is: 194.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    259.61 : 389.31 = 129.50 : x
  2. Step 2: Convert to fraction form
    259.61/389.31 = 129.50/x
  3. Step 3: Cross multiply
    259.61x = 389.31 × 129.50
  4. Step 4: Simplify right side
    259.61x = 50,414.67
  5. Step 5: Solve for x
    x = 50,414.67/259.61
  6. Step 6: Final answer
    x = 194.20

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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.