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Finding the Third Proportional to 405 and 525

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Solution

The third proportional to 405 and 525 is: 680.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    405 : 525 = 525 : x
  2. Step 2: Convert to fraction form
    405/525 = 525/x
  3. Step 3: Cross multiply
    405x = 525 × 525
  4. Step 4: Simplify right side
    405x = 275,625
  5. Step 5: Solve for x
    x = 275,625/405
  6. Step 6: Final answer
    x = 680.56

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Why These Related Problems?

These problems maintain the same ratio (1.30) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.