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Finding the Fourth Proportional to 419.99, 629.91 and 339.30

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Solution

The fourth proportional to 419.99, 629.91 and 339.30 is: 508.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.99 : 629.91 = 339.30 : x
  2. Step 2: Convert to fraction form
    419.99/629.91 = 339.30/x
  3. Step 3: Cross multiply
    419.99x = 629.91 × 339.30
  4. Step 4: Simplify right side
    419.99x = 213,728.46
  5. Step 5: Solve for x
    x = 213,728.46/419.99
  6. Step 6: Final answer
    x = 508.90

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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.