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Finding the Fourth Proportional to 320.28, 480.42 and 103.90

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Solution

The fourth proportional to 320.28, 480.42 and 103.90 is: 155.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.28 : 480.42 = 103.90 : x
  2. Step 2: Convert to fraction form
    320.28/480.42 = 103.90/x
  3. Step 3: Cross multiply
    320.28x = 480.42 × 103.90
  4. Step 4: Simplify right side
    320.28x = 49,915.64
  5. Step 5: Solve for x
    x = 49,915.64/320.28
  6. Step 6: Final answer
    x = 155.85

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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.