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Finding the Fourth Proportional to 445.28, 668.12 and 280.71

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Solution

The fourth proportional to 445.28, 668.12 and 280.71 is: 421.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    445.28 : 668.12 = 280.71 : x
  2. Step 2: Convert to fraction form
    445.28/668.12 = 280.71/x
  3. Step 3: Cross multiply
    445.28x = 668.12 × 280.71
  4. Step 4: Simplify right side
    445.28x = 187,544.62
  5. Step 5: Solve for x
    x = 187,544.62/445.28
  6. Step 6: Final answer
    x = 421.19

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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.