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Finding the Fourth Proportional to 443.28, 665.40 and 280.56

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Solution

The fourth proportional to 443.28, 665.40 and 280.56 is: 421.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    443.28 : 665.40 = 280.56 : x
  2. Step 2: Convert to fraction form
    443.28/665.40 = 280.56/x
  3. Step 3: Cross multiply
    443.28x = 665.40 × 280.56
  4. Step 4: Simplify right side
    443.28x = 186,684.62
  5. Step 5: Solve for x
    x = 186,684.62/443.28
  6. Step 6: Final answer
    x = 421.14

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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.