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Finding the Fourth Proportional to 391.47, 540.19 and 225.64

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Solution

The fourth proportional to 391.47, 540.19 and 225.64 is: 311.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.47 : 540.19 = 225.64 : x
  2. Step 2: Convert to fraction form
    391.47/540.19 = 225.64/x
  3. Step 3: Cross multiply
    391.47x = 540.19 × 225.64
  4. Step 4: Simplify right side
    391.47x = 121,891.58
  5. Step 5: Solve for x
    x = 121,891.58/391.47
  6. Step 6: Final answer
    x = 311.37

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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.