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Finding the Fourth Proportional to 391.14, 538.79 and 328.97

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Solution

The fourth proportional to 391.14, 538.79 and 328.97 is: 453.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.14 : 538.79 = 328.97 : x
  2. Step 2: Convert to fraction form
    391.14/538.79 = 328.97/x
  3. Step 3: Cross multiply
    391.14x = 538.79 × 328.97
  4. Step 4: Simplify right side
    391.14x = 177,245.45
  5. Step 5: Solve for x
    x = 177,245.45/391.14
  6. Step 6: Final answer
    x = 453.15

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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.