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Finding the Third Proportional to 639.50 and 729.50

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Solution

The third proportional to 639.50 and 729.50 is: 832.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.50 : 729.50 = 729.50 : x
  2. Step 2: Convert to fraction form
    639.50/729.50 = 729.50/x
  3. Step 3: Cross multiply
    639.50x = 729.50 × 729.50
  4. Step 4: Simplify right side
    639.50x = 532,170.25
  5. Step 5: Solve for x
    x = 532,170.25/639.50
  6. Step 6: Final answer
    x = 832.17

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Why These Related Problems?

These problems maintain the same ratio (1.14) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.