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Finding the Third Proportional to 387.75 and 513

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Solution

The third proportional to 387.75 and 513 is: 678.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.75 : 513 = 513 : x
  2. Step 2: Convert to fraction form
    387.75/513 = 513/x
  3. Step 3: Cross multiply
    387.75x = 513 × 513
  4. Step 4: Simplify right side
    387.75x = 263,169
  5. Step 5: Solve for x
    x = 263,169/387.75
  6. Step 6: Final answer
    x = 678.71

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Why These Related Problems?

These problems maintain the same ratio (1.32) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.