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Finding the Fourth Proportional to 395.21, 545.42 and 220.55

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Solution

The fourth proportional to 395.21, 545.42 and 220.55 is: 304.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    395.21 : 545.42 = 220.55 : x
  2. Step 2: Convert to fraction form
    395.21/545.42 = 220.55/x
  3. Step 3: Cross multiply
    395.21x = 545.42 × 220.55
  4. Step 4: Simplify right side
    395.21x = 120,292.38
  5. Step 5: Solve for x
    x = 120,292.38/395.21
  6. Step 6: Final answer
    x = 304.38

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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.