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Finding the Third Proportional to 405 and 456

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Solution

The third proportional to 405 and 456 is: 513.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    405 : 456 = 456 : x
  2. Step 2: Convert to fraction form
    405/456 = 456/x
  3. Step 3: Cross multiply
    405x = 456 × 456
  4. Step 4: Simplify right side
    405x = 207,936
  5. Step 5: Solve for x
    x = 207,936/405
  6. Step 6: Final answer
    x = 513.42

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Why These Related Problems?

These problems maintain the same ratio (1.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.