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Finding the Third Proportional to 687 and 745

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Solution

The third proportional to 687 and 745 is: 807.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    687 : 745 = 745 : x
  2. Step 2: Convert to fraction form
    687/745 = 745/x
  3. Step 3: Cross multiply
    687x = 745 × 745
  4. Step 4: Simplify right side
    687x = 555,025
  5. Step 5: Solve for x
    x = 555,025/687
  6. Step 6: Final answer
    x = 807.90

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Why These Related Problems?

These problems maintain the same ratio (1.08) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.