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Finding the Fourth Proportional to 129.71, 178.96 and 77.23

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Solution

The fourth proportional to 129.71, 178.96 and 77.23 is: 106.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    129.71 : 178.96 = 77.23 : x
  2. Step 2: Convert to fraction form
    129.71/178.96 = 77.23/x
  3. Step 3: Cross multiply
    129.71x = 178.96 × 77.23
  4. Step 4: Simplify right side
    129.71x = 13,820.69
  5. Step 5: Solve for x
    x = 13,820.69/129.71
  6. Step 6: Final answer
    x = 106.55

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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.