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Finding the Fourth Proportional to 86, 129 and 29

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Solution

The fourth proportional to 86, 129 and 29 is: 43.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    86 : 129 = 29 : x
  2. Step 2: Convert to fraction form
    86/129 = 29/x
  3. Step 3: Cross multiply
    86x = 129 × 29
  4. Step 4: Simplify right side
    86x = 3,741
  5. Step 5: Solve for x
    x = 3,741/86
  6. Step 6: Final answer
    x = 43.50

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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.