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Finding the Third Proportional to 399 and 619

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Solution

The third proportional to 399 and 619 is: 960.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    399 : 619 = 619 : x
  2. Step 2: Convert to fraction form
    399/619 = 619/x
  3. Step 3: Cross multiply
    399x = 619 × 619
  4. Step 4: Simplify right side
    399x = 383,161
  5. Step 5: Solve for x
    x = 383,161/399
  6. Step 6: Final answer
    x = 960.30

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Why These Related Problems?

These problems maintain the same ratio (1.55) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.