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Finding the Third Proportional to 359 and 391

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Solution

The third proportional to 359 and 391 is: 425.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    359 : 391 = 391 : x
  2. Step 2: Convert to fraction form
    359/391 = 391/x
  3. Step 3: Cross multiply
    359x = 391 × 391
  4. Step 4: Simplify right side
    359x = 152,881
  5. Step 5: Solve for x
    x = 152,881/359
  6. Step 6: Final answer
    x = 425.85

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Why These Related Problems?

These problems maintain the same ratio (1.09) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.