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Finding the Fourth Proportional to 320.20, 480.30 and 103.78

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Solution

The fourth proportional to 320.20, 480.30 and 103.78 is: 155.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.20 : 480.30 = 103.78 : x
  2. Step 2: Convert to fraction form
    320.20/480.30 = 103.78/x
  3. Step 3: Cross multiply
    320.20x = 480.30 × 103.78
  4. Step 4: Simplify right side
    320.20x = 49,846.62
  5. Step 5: Solve for x
    x = 49,846.62/320.20
  6. Step 6: Final answer
    x = 155.67

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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.