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Finding the Fourth Proportional to 418.09, 627.30 and 129.55

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Solution

The fourth proportional to 418.09, 627.30 and 129.55 is: 194.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.09 : 627.30 = 129.55 : x
  2. Step 2: Convert to fraction form
    418.09/627.30 = 129.55/x
  3. Step 3: Cross multiply
    418.09x = 627.30 × 129.55
  4. Step 4: Simplify right side
    418.09x = 81,266.72
  5. Step 5: Solve for x
    x = 81,266.72/418.09
  6. Step 6: Final answer
    x = 194.38

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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.