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Finding the Third Proportional to 687 and 800

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Solution

The third proportional to 687 and 800 is: 931.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    687 : 800 = 800 : x
  2. Step 2: Convert to fraction form
    687/800 = 800/x
  3. Step 3: Cross multiply
    687x = 800 × 800
  4. Step 4: Simplify right side
    687x = 640,000
  5. Step 5: Solve for x
    x = 640,000/687
  6. Step 6: Final answer
    x = 931.59

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Why These Related Problems?

These problems maintain the same ratio (1.16) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.