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Finding the Fourth Proportional to 125.55, 173.11 and 78.91

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Solution

The fourth proportional to 125.55, 173.11 and 78.91 is: 108.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    125.55 : 173.11 = 78.91 : x
  2. Step 2: Convert to fraction form
    125.55/173.11 = 78.91/x
  3. Step 3: Cross multiply
    125.55x = 173.11 × 78.91
  4. Step 4: Simplify right side
    125.55x = 13,658.85
  5. Step 5: Solve for x
    x = 13,658.85/125.55
  6. Step 6: Final answer
    x = 108.80

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.