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Finding the Fourth Proportional to 391.10, 538.83 and 321.17

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Solution

The fourth proportional to 391.10, 538.83 and 321.17 is: 442.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.10 : 538.83 = 321.17 : x
  2. Step 2: Convert to fraction form
    391.10/538.83 = 321.17/x
  3. Step 3: Cross multiply
    391.10x = 538.83 × 321.17
  4. Step 4: Simplify right side
    391.10x = 173,053.34
  5. Step 5: Solve for x
    x = 173,053.34/391.10
  6. Step 6: Final answer
    x = 442.48

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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.