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Finding the Fourth Proportional to 145.98, 217.86 and 129.78

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Solution

The fourth proportional to 145.98, 217.86 and 129.78 is: 193.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.98 : 217.86 = 129.78 : x
  2. Step 2: Convert to fraction form
    145.98/217.86 = 129.78/x
  3. Step 3: Cross multiply
    145.98x = 217.86 × 129.78
  4. Step 4: Simplify right side
    145.98x = 28,273.87
  5. Step 5: Solve for x
    x = 28,273.87/145.98
  6. Step 6: Final answer
    x = 193.68

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.