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Finding the Fourth Proportional to 480.72, 720.38 and 378.21

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Solution

The fourth proportional to 480.72, 720.38 and 378.21 is: 566.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    480.72 : 720.38 = 378.21 : x
  2. Step 2: Convert to fraction form
    480.72/720.38 = 378.21/x
  3. Step 3: Cross multiply
    480.72x = 720.38 × 378.21
  4. Step 4: Simplify right side
    480.72x = 272,452.97
  5. Step 5: Solve for x
    x = 272,452.97/480.72
  6. Step 6: Final answer
    x = 566.76

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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.