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Finding the Fourth Proportional to 393.20, 589.39 and 256.31

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Solution

The fourth proportional to 393.20, 589.39 and 256.31 is: 384.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    393.20 : 589.39 = 256.31 : x
  2. Step 2: Convert to fraction form
    393.20/589.39 = 256.31/x
  3. Step 3: Cross multiply
    393.20x = 589.39 × 256.31
  4. Step 4: Simplify right side
    393.20x = 151,065.27
  5. Step 5: Solve for x
    x = 151,065.27/393.20
  6. Step 6: Final answer
    x = 384.19

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.