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Finding the Fourth Proportional to 403.65, 605.52 and 129.78

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Solution

The fourth proportional to 403.65, 605.52 and 129.78 is: 194.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.65 : 605.52 = 129.78 : x
  2. Step 2: Convert to fraction form
    403.65/605.52 = 129.78/x
  3. Step 3: Cross multiply
    403.65x = 605.52 × 129.78
  4. Step 4: Simplify right side
    403.65x = 78,584.39
  5. Step 5: Solve for x
    x = 78,584.39/403.65
  6. Step 6: Final answer
    x = 194.68

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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.