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Finding the Fourth Proportional to 391.23, 539.36 and 286.18

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Solution

The fourth proportional to 391.23, 539.36 and 286.18 is: 394.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.23 : 539.36 = 286.18 : x
  2. Step 2: Convert to fraction form
    391.23/539.36 = 286.18/x
  3. Step 3: Cross multiply
    391.23x = 539.36 × 286.18
  4. Step 4: Simplify right side
    391.23x = 154,355.37
  5. Step 5: Solve for x
    x = 154,355.37/391.23
  6. Step 6: Final answer
    x = 394.54

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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.