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Finding the Fourth Proportional to 129.80, 194.82 and 120.86

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Solution

The fourth proportional to 129.80, 194.82 and 120.86 is: 181.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    129.80 : 194.82 = 120.86 : x
  2. Step 2: Convert to fraction form
    129.80/194.82 = 120.86/x
  3. Step 3: Cross multiply
    129.80x = 194.82 × 120.86
  4. Step 4: Simplify right side
    129.80x = 23,545.95
  5. Step 5: Solve for x
    x = 23,545.95/129.80
  6. Step 6: Final answer
    x = 181.40

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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.