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Finding the Third Proportional to 402 and 509

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Solution

The third proportional to 402 and 509 is: 644.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    402 : 509 = 509 : x
  2. Step 2: Convert to fraction form
    402/509 = 509/x
  3. Step 3: Cross multiply
    402x = 509 × 509
  4. Step 4: Simplify right side
    402x = 259,081
  5. Step 5: Solve for x
    x = 259,081/402
  6. Step 6: Final answer
    x = 644.48

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Why These Related Problems?

These problems maintain the same ratio (1.27) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.