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Finding the Fourth Proportional to 447.40, 618.85 and 378.55

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Solution

The fourth proportional to 447.40, 618.85 and 378.55 is: 523.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    447.40 : 618.85 = 378.55 : x
  2. Step 2: Convert to fraction form
    447.40/618.85 = 378.55/x
  3. Step 3: Cross multiply
    447.40x = 618.85 × 378.55
  4. Step 4: Simplify right side
    447.40x = 234,262.57
  5. Step 5: Solve for x
    x = 234,262.57/447.40
  6. Step 6: Final answer
    x = 523.61

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.