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Finding the Third Proportional to 399 and 488

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Solution

The third proportional to 399 and 488 is: 596.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    399 : 488 = 488 : x
  2. Step 2: Convert to fraction form
    399/488 = 488/x
  3. Step 3: Cross multiply
    399x = 488 × 488
  4. Step 4: Simplify right side
    399x = 238,144
  5. Step 5: Solve for x
    x = 238,144/399
  6. Step 6: Final answer
    x = 596.85

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Why These Related Problems?

These problems maintain the same ratio (1.22) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.