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Finding the Fourth Proportional to 321.28, 443.66 and 286.31

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Solution

The fourth proportional to 321.28, 443.66 and 286.31 is: 395.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    321.28 : 443.66 = 286.31 : x
  2. Step 2: Convert to fraction form
    321.28/443.66 = 286.31/x
  3. Step 3: Cross multiply
    321.28x = 443.66 × 286.31
  4. Step 4: Simplify right side
    321.28x = 127,022.86
  5. Step 5: Solve for x
    x = 127,022.86/321.28
  6. Step 6: Final answer
    x = 395.37

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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.