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Finding the Third Proportional to 312 and 648

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Solution

The third proportional to 312 and 648 is: 1,345.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    312 : 648 = 648 : x
  2. Step 2: Convert to fraction form
    312/648 = 648/x
  3. Step 3: Cross multiply
    312x = 648 × 648
  4. Step 4: Simplify right side
    312x = 419,904
  5. Step 5: Solve for x
    x = 419,904/312
  6. Step 6: Final answer
    x = 1,345.85

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Why These Related Problems?

These problems maintain the same ratio (2.08) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.