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Finding the Fourth Proportional to 120.29, 180.35 and 39.09

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Solution

The fourth proportional to 120.29, 180.35 and 39.09 is: 58.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.29 : 180.35 = 39.09 : x
  2. Step 2: Convert to fraction form
    120.29/180.35 = 39.09/x
  3. Step 3: Cross multiply
    120.29x = 180.35 × 39.09
  4. Step 4: Simplify right side
    120.29x = 7,049.88
  5. Step 5: Solve for x
    x = 7,049.88/120.29
  6. Step 6: Final answer
    x = 58.61

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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.