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Finding the Fourth Proportional to 391.47, 587.34 and 281.58

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Solution

The fourth proportional to 391.47, 587.34 and 281.58 is: 422.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.47 : 587.34 = 281.58 : x
  2. Step 2: Convert to fraction form
    391.47/587.34 = 281.58/x
  3. Step 3: Cross multiply
    391.47x = 587.34 × 281.58
  4. Step 4: Simplify right side
    391.47x = 165,383.20
  5. Step 5: Solve for x
    x = 165,383.20/391.47
  6. Step 6: Final answer
    x = 422.47

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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.