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Finding the Fourth Proportional to 390.05, 585.03 and 146.55

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Solution

The fourth proportional to 390.05, 585.03 and 146.55 is: 219.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.05 : 585.03 = 146.55 : x
  2. Step 2: Convert to fraction form
    390.05/585.03 = 146.55/x
  3. Step 3: Cross multiply
    390.05x = 585.03 × 146.55
  4. Step 4: Simplify right side
    390.05x = 85,736.15
  5. Step 5: Solve for x
    x = 85,736.15/390.05
  6. Step 6: Final answer
    x = 219.81

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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.