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Finding the Fourth Proportional to 665.07, 996.36 and 421.09

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Solution

The fourth proportional to 665.07, 996.36 and 421.09 is: 630.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.07 : 996.36 = 421.09 : x
  2. Step 2: Convert to fraction form
    665.07/996.36 = 421.09/x
  3. Step 3: Cross multiply
    665.07x = 996.36 × 421.09
  4. Step 4: Simplify right side
    665.07x = 419,557.23
  5. Step 5: Solve for x
    x = 419,557.23/665.07
  6. Step 6: Final answer
    x = 630.85

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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.