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Finding the Fourth Proportional to 390.20, 585.14 and 146.60

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Solution

The fourth proportional to 390.20, 585.14 and 146.60 is: 219.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.20 : 585.14 = 146.60 : x
  2. Step 2: Convert to fraction form
    390.20/585.14 = 146.60/x
  3. Step 3: Cross multiply
    390.20x = 585.14 × 146.60
  4. Step 4: Simplify right side
    390.20x = 85,778.60
  5. Step 5: Solve for x
    x = 85,778.60/390.20
  6. Step 6: Final answer
    x = 219.83

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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.