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Finding the Fourth Proportional to 420.11, 629.65 and 327.85

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Solution

The fourth proportional to 420.11, 629.65 and 327.85 is: 491.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.11 : 629.65 = 327.85 : x
  2. Step 2: Convert to fraction form
    420.11/629.65 = 327.85/x
  3. Step 3: Cross multiply
    420.11x = 629.65 × 327.85
  4. Step 4: Simplify right side
    420.11x = 206,428.67
  5. Step 5: Solve for x
    x = 206,428.67/420.11
  6. Step 6: Final answer
    x = 491.37

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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.