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Finding the Third Proportional to 287 and 393

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Solution

The third proportional to 287 and 393 is: 538.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    287 : 393 = 393 : x
  2. Step 2: Convert to fraction form
    287/393 = 393/x
  3. Step 3: Cross multiply
    287x = 393 × 393
  4. Step 4: Simplify right side
    287x = 154,449
  5. Step 5: Solve for x
    x = 154,449/287
  6. Step 6: Final answer
    x = 538.15

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.