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Finding the Third Proportional to 387.75 and 561.75

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Solution

The third proportional to 387.75 and 561.75 is: 813.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.75 : 561.75 = 561.75 : x
  2. Step 2: Convert to fraction form
    387.75/561.75 = 561.75/x
  3. Step 3: Cross multiply
    387.75x = 561.75 × 561.75
  4. Step 4: Simplify right side
    387.75x = 315,563.06
  5. Step 5: Solve for x
    x = 315,563.06/387.75
  6. Step 6: Final answer
    x = 813.83

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Why These Related Problems?

These problems maintain the same ratio (1.45) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.