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Finding the Fourth Proportional to 420.11, 629.82 and 329.21

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Solution

The fourth proportional to 420.11, 629.82 and 329.21 is: 493.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.11 : 629.82 = 329.21 : x
  2. Step 2: Convert to fraction form
    420.11/629.82 = 329.21/x
  3. Step 3: Cross multiply
    420.11x = 629.82 × 329.21
  4. Step 4: Simplify right side
    420.11x = 207,341.40
  5. Step 5: Solve for x
    x = 207,341.40/420.11
  6. Step 6: Final answer
    x = 493.55

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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.