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Finding the Fourth Proportional to 420.34, 629.49 and 339.34

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Solution

The fourth proportional to 420.34, 629.49 and 339.34 is: 508.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.34 : 629.49 = 339.34 : x
  2. Step 2: Convert to fraction form
    420.34/629.49 = 339.34/x
  3. Step 3: Cross multiply
    420.34x = 629.49 × 339.34
  4. Step 4: Simplify right side
    420.34x = 213,610.84
  5. Step 5: Solve for x
    x = 213,610.84/420.34
  6. Step 6: Final answer
    x = 508.19

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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.