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Finding the Third Proportional to 309 and 343

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Solution

The third proportional to 309 and 343 is: 380.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    309 : 343 = 343 : x
  2. Step 2: Convert to fraction form
    309/343 = 343/x
  3. Step 3: Cross multiply
    309x = 343 × 343
  4. Step 4: Simplify right side
    309x = 117,649
  5. Step 5: Solve for x
    x = 117,649/309
  6. Step 6: Final answer
    x = 380.74

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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.