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Finding the Third Proportional to 553 and 647

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Solution

The third proportional to 553 and 647 is: 756.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    553 : 647 = 647 : x
  2. Step 2: Convert to fraction form
    553/647 = 647/x
  3. Step 3: Cross multiply
    553x = 647 × 647
  4. Step 4: Simplify right side
    553x = 418,609
  5. Step 5: Solve for x
    x = 418,609/553
  6. Step 6: Final answer
    x = 756.98

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Why These Related Problems?

These problems maintain the same ratio (1.17) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.