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Finding the Third Proportional to 509 and 521

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Solution

The third proportional to 509 and 521 is: 533.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    509 : 521 = 521 : x
  2. Step 2: Convert to fraction form
    509/521 = 521/x
  3. Step 3: Cross multiply
    509x = 521 × 521
  4. Step 4: Simplify right side
    509x = 271,441
  5. Step 5: Solve for x
    x = 271,441/509
  6. Step 6: Final answer
    x = 533.28

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Why These Related Problems?

These problems maintain the same ratio (1.02) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.