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Finding the Fourth Proportional to 391.43, 587.12 and 185.87

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Solution

The fourth proportional to 391.43, 587.12 and 185.87 is: 278.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.43 : 587.12 = 185.87 : x
  2. Step 2: Convert to fraction form
    391.43/587.12 = 185.87/x
  3. Step 3: Cross multiply
    391.43x = 587.12 × 185.87
  4. Step 4: Simplify right side
    391.43x = 109,128.53
  5. Step 5: Solve for x
    x = 109,128.53/391.43
  6. Step 6: Final answer
    x = 278.79

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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.