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Finding the Fourth Proportional to 664.40, 996.71 and 339.66

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Solution

The fourth proportional to 664.40, 996.71 and 339.66 is: 509.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    664.40 : 996.71 = 339.66 : x
  2. Step 2: Convert to fraction form
    664.40/996.71 = 339.66/x
  3. Step 3: Cross multiply
    664.40x = 996.71 × 339.66
  4. Step 4: Simplify right side
    664.40x = 338,540.82
  5. Step 5: Solve for x
    x = 338,540.82/664.40
  6. Step 6: Final answer
    x = 509.54

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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.