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Finding the Third Proportional to 78 and 137

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Solution

The third proportional to 78 and 137 is: 240.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    78 : 137 = 137 : x
  2. Step 2: Convert to fraction form
    78/137 = 137/x
  3. Step 3: Cross multiply
    78x = 137 × 137
  4. Step 4: Simplify right side
    78x = 18,769
  5. Step 5: Solve for x
    x = 18,769/78
  6. Step 6: Final answer
    x = 240.63

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Why These Related Problems?

These problems maintain the same ratio (1.76) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.