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Finding the Third Proportional to 309 and 676

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Solution

The third proportional to 309 and 676 is: 1,478.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    309 : 676 = 676 : x
  2. Step 2: Convert to fraction form
    309/676 = 676/x
  3. Step 3: Cross multiply
    309x = 676 × 676
  4. Step 4: Simplify right side
    309x = 456,976
  5. Step 5: Solve for x
    x = 456,976/309
  6. Step 6: Final answer
    x = 1,478.89

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Why These Related Problems?

These problems maintain the same ratio (2.19) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.