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Finding the Third Proportional to 309.09 and 613.69

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Solution

The third proportional to 309.09 and 613.69 is: 1,218.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.09 : 613.69 = 613.69 : x
  2. Step 2: Convert to fraction form
    309.09/613.69 = 613.69/x
  3. Step 3: Cross multiply
    309.09x = 613.69 × 613.69
  4. Step 4: Simplify right side
    309.09x = 376,612.35
  5. Step 5: Solve for x
    x = 376,612.35/309.09
  6. Step 6: Final answer
    x = 1,218.44

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Why These Related Problems?

These problems maintain the same ratio (1.99) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.