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Finding the Third Proportional to 285 and 431

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Solution

The third proportional to 285 and 431 is: 651.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    285 : 431 = 431 : x
  2. Step 2: Convert to fraction form
    285/431 = 431/x
  3. Step 3: Cross multiply
    285x = 431 × 431
  4. Step 4: Simplify right side
    285x = 185,761
  5. Step 5: Solve for x
    x = 185,761/285
  6. Step 6: Final answer
    x = 651.79

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.