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Finding the Third Proportional to 309.50 and 679

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Solution

The third proportional to 309.50 and 679 is: 1,489.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.50 : 679 = 679 : x
  2. Step 2: Convert to fraction form
    309.50/679 = 679/x
  3. Step 3: Cross multiply
    309.50x = 679 × 679
  4. Step 4: Simplify right side
    309.50x = 461,041
  5. Step 5: Solve for x
    x = 461,041/309.50
  6. Step 6: Final answer
    x = 1,489.63

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Why These Related Problems?

These problems maintain the same ratio (2.19) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.