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Finding the Third Proportional to 396 and 555

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Solution

The third proportional to 396 and 555 is: 777.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    396 : 555 = 555 : x
  2. Step 2: Convert to fraction form
    396/555 = 555/x
  3. Step 3: Cross multiply
    396x = 555 × 555
  4. Step 4: Simplify right side
    396x = 308,025
  5. Step 5: Solve for x
    x = 308,025/396
  6. Step 6: Final answer
    x = 777.84

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Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.