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Finding the Fourth Proportional to 385.82, 578.28 and 320.72

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Solution

The fourth proportional to 385.82, 578.28 and 320.72 is: 480.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.82 : 578.28 = 320.72 : x
  2. Step 2: Convert to fraction form
    385.82/578.28 = 320.72/x
  3. Step 3: Cross multiply
    385.82x = 578.28 × 320.72
  4. Step 4: Simplify right side
    385.82x = 185,465.96
  5. Step 5: Solve for x
    x = 185,465.96/385.82
  6. Step 6: Final answer
    x = 480.71

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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.