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Finding the Third Proportional to 128 and 330

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Solution

The third proportional to 128 and 330 is: 850.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    128 : 330 = 330 : x
  2. Step 2: Convert to fraction form
    128/330 = 330/x
  3. Step 3: Cross multiply
    128x = 330 × 330
  4. Step 4: Simplify right side
    128x = 108,900
  5. Step 5: Solve for x
    x = 108,900/128
  6. Step 6: Final answer
    x = 850.78

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Why These Related Problems?

These problems maintain the same ratio (2.58) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.