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Finding the Fourth Proportional to 391.05, 539.53 and 225.20

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Solution

The fourth proportional to 391.05, 539.53 and 225.20 is: 310.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.05 : 539.53 = 225.20 : x
  2. Step 2: Convert to fraction form
    391.05/539.53 = 225.20/x
  3. Step 3: Cross multiply
    391.05x = 539.53 × 225.20
  4. Step 4: Simplify right side
    391.05x = 121,502.94
  5. Step 5: Solve for x
    x = 121,502.94/391.05
  6. Step 6: Final answer
    x = 310.71

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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.