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Finding the Fourth Proportional to 391.68, 540.71 and 225.86

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Solution

The fourth proportional to 391.68, 540.71 and 225.86 is: 311.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.68 : 540.71 = 225.86 : x
  2. Step 2: Convert to fraction form
    391.68/540.71 = 225.86/x
  3. Step 3: Cross multiply
    391.68x = 540.71 × 225.86
  4. Step 4: Simplify right side
    391.68x = 122,120.93
  5. Step 5: Solve for x
    x = 122,120.93/391.68
  6. Step 6: Final answer
    x = 311.79

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.