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Finding the Fourth Proportional to 339.90, 509.89 and 123.45

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Solution

The fourth proportional to 339.90, 509.89 and 123.45 is: 185.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.90 : 509.89 = 123.45 : x
  2. Step 2: Convert to fraction form
    339.90/509.89 = 123.45/x
  3. Step 3: Cross multiply
    339.90x = 509.89 × 123.45
  4. Step 4: Simplify right side
    339.90x = 62,945.92
  5. Step 5: Solve for x
    x = 62,945.92/339.90
  6. Step 6: Final answer
    x = 185.19

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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.