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Finding the Fourth Proportional to 621.20, 928.25 and 447.05

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Solution

The fourth proportional to 621.20, 928.25 and 447.05 is: 668.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.20 : 928.25 = 447.05 : x
  2. Step 2: Convert to fraction form
    621.20/928.25 = 447.05/x
  3. Step 3: Cross multiply
    621.20x = 928.25 × 447.05
  4. Step 4: Simplify right side
    621.20x = 414,974.16
  5. Step 5: Solve for x
    x = 414,974.16/621.20
  6. Step 6: Final answer
    x = 668.02

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.