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Finding the Third Proportional to 138,240 and 213,840

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Solution

The third proportional to 138,240 and 213,840 is: 330,783.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    138,240 : 213,840 = 213,840 : x
  2. Step 2: Convert to fraction form
    138,240/213,840 = 213,840/x
  3. Step 3: Cross multiply
    138,240x = 213,840 × 213,840
  4. Step 4: Simplify right side
    138,240x = 45,727,545,600
  5. Step 5: Solve for x
    x = 45,727,545,600/138,240
  6. Step 6: Final answer
    x = 330,783.75

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Why These Related Problems?

These problems maintain the same ratio (1.55) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.