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Finding the Fourth Proportional to 320.95, 479.25 and 255.21

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Solution

The fourth proportional to 320.95, 479.25 and 255.21 is: 381.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.95 : 479.25 = 255.21 : x
  2. Step 2: Convert to fraction form
    320.95/479.25 = 255.21/x
  3. Step 3: Cross multiply
    320.95x = 479.25 × 255.21
  4. Step 4: Simplify right side
    320.95x = 122,309.39
  5. Step 5: Solve for x
    x = 122,309.39/320.95
  6. Step 6: Final answer
    x = 381.09

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.