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Finding the Fourth Proportional to 665.37, 997.03 and 421.39

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Solution

The fourth proportional to 665.37, 997.03 and 421.39 is: 631.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.37 : 997.03 = 421.39 : x
  2. Step 2: Convert to fraction form
    665.37/997.03 = 421.39/x
  3. Step 3: Cross multiply
    665.37x = 997.03 × 421.39
  4. Step 4: Simplify right side
    665.37x = 420,135.89
  5. Step 5: Solve for x
    x = 420,135.89/665.37
  6. Step 6: Final answer
    x = 631.43

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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.