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Finding the Fourth Proportional to 386.32, 579.47 and 129.82

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Solution

The fourth proportional to 386.32, 579.47 and 129.82 is: 194.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.32 : 579.47 = 129.82 : x
  2. Step 2: Convert to fraction form
    386.32/579.47 = 129.82/x
  3. Step 3: Cross multiply
    386.32x = 579.47 × 129.82
  4. Step 4: Simplify right side
    386.32x = 75,226.15
  5. Step 5: Solve for x
    x = 75,226.15/386.32
  6. Step 6: Final answer
    x = 194.72

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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.