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Finding the Fourth Proportional to 71.91, 107.86 and 29.19

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Solution

The fourth proportional to 71.91, 107.86 and 29.19 is: 43.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.91 : 107.86 = 29.19 : x
  2. Step 2: Convert to fraction form
    71.91/107.86 = 29.19/x
  3. Step 3: Cross multiply
    71.91x = 107.86 × 29.19
  4. Step 4: Simplify right side
    71.91x = 3,147.82
  5. Step 5: Solve for x
    x = 3,147.82/71.91
  6. Step 6: Final answer
    x = 43.78

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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.