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Finding the Third Proportional to 140.81 and 309.19

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Solution

The third proportional to 140.81 and 309.19 is: 678.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    140.81 : 309.19 = 309.19 : x
  2. Step 2: Convert to fraction form
    140.81/309.19 = 309.19/x
  3. Step 3: Cross multiply
    140.81x = 309.19 × 309.19
  4. Step 4: Simplify right side
    140.81x = 95,596.91
  5. Step 5: Solve for x
    x = 95,596.91/140.81
  6. Step 6: Final answer
    x = 678.90

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Why These Related Problems?

These problems maintain the same ratio (2.20) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.