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Finding the Third Proportional to 639.56 and 1,287.56

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Solution

The third proportional to 639.56 and 1,287.56 is: 2,592.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.56 : 1,287.56 = 1,287.56 : x
  2. Step 2: Convert to fraction form
    639.56/1,287.56 = 1,287.56/x
  3. Step 3: Cross multiply
    639.56x = 1,287.56 × 1,287.56
  4. Step 4: Simplify right side
    639.56x = 1,657,817.19
  5. Step 5: Solve for x
    x = 1,657,817.19/639.56
  6. Step 6: Final answer
    x = 2,592.11

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Why These Related Problems?

These problems maintain the same ratio (2.01) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.