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Finding the Third Proportional to 387 and 698

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Solution

The third proportional to 387 and 698 is: 1,258.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    387 : 698 = 698 : x
  2. Step 2: Convert to fraction form
    387/698 = 698/x
  3. Step 3: Cross multiply
    387x = 698 × 698
  4. Step 4: Simplify right side
    387x = 487,204
  5. Step 5: Solve for x
    x = 487,204/387
  6. Step 6: Final answer
    x = 1,258.93

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These problems maintain the same ratio (1.80) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.