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Finding the Third Proportional to 729 and 810

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Solution

The third proportional to 729 and 810 is: 900

Step by Step Solution

  1. Step 1: Write the proportion equation
    729 : 810 = 810 : x
  2. Step 2: Convert to fraction form
    729/810 = 810/x
  3. Step 3: Cross multiply
    729x = 810 × 810
  4. Step 4: Simplify right side
    729x = 656,100
  5. Step 5: Solve for x
    x = 656,100/729
  6. Step 6: Final answer
    x = 900

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Why These Related Problems?

These problems maintain the same ratio (1.11) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.