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Finding the Fourth Proportional to 391.26, 539.12 and 321.10

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Solution

The fourth proportional to 391.26, 539.12 and 321.10 is: 442.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.26 : 539.12 = 321.10 : x
  2. Step 2: Convert to fraction form
    391.26/539.12 = 321.10/x
  3. Step 3: Cross multiply
    391.26x = 539.12 × 321.10
  4. Step 4: Simplify right side
    391.26x = 173,111.43
  5. Step 5: Solve for x
    x = 173,111.43/391.26
  6. Step 6: Final answer
    x = 442.45

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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.