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Finding the Fourth Proportional to 665, 997.50 and 280.26

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Solution

The fourth proportional to 665, 997.50 and 280.26 is: 420.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    665 : 997.50 = 280.26 : x
  2. Step 2: Convert to fraction form
    665/997.50 = 280.26/x
  3. Step 3: Cross multiply
    665x = 997.50 × 280.26
  4. Step 4: Simplify right side
    665x = 279,559.35
  5. Step 5: Solve for x
    x = 279,559.35/665
  6. Step 6: Final answer
    x = 420.39

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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.