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Finding the Fourth Proportional to 130.55, 195.89 and 81.90

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Solution

The fourth proportional to 130.55, 195.89 and 81.90 is: 122.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    130.55 : 195.89 = 81.90 : x
  2. Step 2: Convert to fraction form
    130.55/195.89 = 81.90/x
  3. Step 3: Cross multiply
    130.55x = 195.89 × 81.90
  4. Step 4: Simplify right side
    130.55x = 16,042.98
  5. Step 5: Solve for x
    x = 16,042.98/130.55
  6. Step 6: Final answer
    x = 122.89

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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.