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Finding the Fourth Proportional to 125.38, 173.09 and 78.78

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Solution

The fourth proportional to 125.38, 173.09 and 78.78 is: 108.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    125.38 : 173.09 = 78.78 : x
  2. Step 2: Convert to fraction form
    125.38/173.09 = 78.78/x
  3. Step 3: Cross multiply
    125.38x = 173.09 × 78.78
  4. Step 4: Simplify right side
    125.38x = 13,636.03
  5. Step 5: Solve for x
    x = 13,636.03/125.38
  6. Step 6: Final answer
    x = 108.76

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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.