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Finding the Third Proportional to 391.31 and 513.56

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Solution

The third proportional to 391.31 and 513.56 is: 674.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.31 : 513.56 = 513.56 : x
  2. Step 2: Convert to fraction form
    391.31/513.56 = 513.56/x
  3. Step 3: Cross multiply
    391.31x = 513.56 × 513.56
  4. Step 4: Simplify right side
    391.31x = 263,746.44
  5. Step 5: Solve for x
    x = 263,746.44/391.31
  6. Step 6: Final answer
    x = 674.00

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Why These Related Problems?

These problems maintain the same ratio (1.31) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.