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Finding the Fourth Proportional to 145.20, 216.68 and 129.82

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Solution

The fourth proportional to 145.20, 216.68 and 129.82 is: 193.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.20 : 216.68 = 129.82 : x
  2. Step 2: Convert to fraction form
    145.20/216.68 = 129.82/x
  3. Step 3: Cross multiply
    145.20x = 216.68 × 129.82
  4. Step 4: Simplify right side
    145.20x = 28,129.40
  5. Step 5: Solve for x
    x = 28,129.40/145.20
  6. Step 6: Final answer
    x = 193.73

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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.