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Finding the Third Proportional to 128.71 and 204.65

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Solution

The third proportional to 128.71 and 204.65 is: 325.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.71 : 204.65 = 204.65 : x
  2. Step 2: Convert to fraction form
    128.71/204.65 = 204.65/x
  3. Step 3: Cross multiply
    128.71x = 204.65 × 204.65
  4. Step 4: Simplify right side
    128.71x = 41,879.83
  5. Step 5: Solve for x
    x = 41,879.83/128.71
  6. Step 6: Final answer
    x = 325.39

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Why These Related Problems?

These problems maintain the same ratio (1.59) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.