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Finding the Third Proportional to 428.69 and 660.88

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Solution

The third proportional to 428.69 and 660.88 is: 1,018.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.69 : 660.88 = 660.88 : x
  2. Step 2: Convert to fraction form
    428.69/660.88 = 660.88/x
  3. Step 3: Cross multiply
    428.69x = 660.88 × 660.88
  4. Step 4: Simplify right side
    428.69x = 436,755.77
  5. Step 5: Solve for x
    x = 436,755.77/428.69
  6. Step 6: Final answer
    x = 1,018.82

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Why These Related Problems?

These problems maintain the same ratio (1.54) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.