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Finding the Fourth Proportional to 390.85, 587.39 and 364.55

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Solution

The fourth proportional to 390.85, 587.39 and 364.55 is: 547.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.85 : 587.39 = 364.55 : x
  2. Step 2: Convert to fraction form
    390.85/587.39 = 364.55/x
  3. Step 3: Cross multiply
    390.85x = 587.39 × 364.55
  4. Step 4: Simplify right side
    390.85x = 214,128.26
  5. Step 5: Solve for x
    x = 214,128.26/390.85
  6. Step 6: Final answer
    x = 547.86

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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.