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Finding the Fourth Proportional to 665.18, 997.78 and 280.44

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Solution

The fourth proportional to 665.18, 997.78 and 280.44 is: 420.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.18 : 997.78 = 280.44 : x
  2. Step 2: Convert to fraction form
    665.18/997.78 = 280.44/x
  3. Step 3: Cross multiply
    665.18x = 997.78 × 280.44
  4. Step 4: Simplify right side
    665.18x = 279,817.42
  5. Step 5: Solve for x
    x = 279,817.42/665.18
  6. Step 6: Final answer
    x = 420.66

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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.