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Finding the Fourth Proportional to 391.61, 587.42 and 229.21

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Solution

The fourth proportional to 391.61, 587.42 and 229.21 is: 343.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.61 : 587.42 = 229.21 : x
  2. Step 2: Convert to fraction form
    391.61/587.42 = 229.21/x
  3. Step 3: Cross multiply
    391.61x = 587.42 × 229.21
  4. Step 4: Simplify right side
    391.61x = 134,642.54
  5. Step 5: Solve for x
    x = 134,642.54/391.61
  6. Step 6: Final answer
    x = 343.82

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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.