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Finding the Fourth Proportional to 129.90, 179.26 and 71.69

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Solution

The fourth proportional to 129.90, 179.26 and 71.69 is: 98.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    129.90 : 179.26 = 71.69 : x
  2. Step 2: Convert to fraction form
    129.90/179.26 = 71.69/x
  3. Step 3: Cross multiply
    129.90x = 179.26 × 71.69
  4. Step 4: Simplify right side
    129.90x = 12,850.48
  5. Step 5: Solve for x
    x = 12,850.48/129.90
  6. Step 6: Final answer
    x = 98.92

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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.