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Finding the Fourth Proportional to 391.63, 538.24 and 380.69

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Solution

The fourth proportional to 391.63, 538.24 and 380.69 is: 523.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.63 : 538.24 = 380.69 : x
  2. Step 2: Convert to fraction form
    391.63/538.24 = 380.69/x
  3. Step 3: Cross multiply
    391.63x = 538.24 × 380.69
  4. Step 4: Simplify right side
    391.63x = 204,902.98
  5. Step 5: Solve for x
    x = 204,902.98/391.63
  6. Step 6: Final answer
    x = 523.21

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.