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Finding the Third Proportional to 399 and 625

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Solution

The third proportional to 399 and 625 is: 979.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    399 : 625 = 625 : x
  2. Step 2: Convert to fraction form
    399/625 = 625/x
  3. Step 3: Cross multiply
    399x = 625 × 625
  4. Step 4: Simplify right side
    399x = 390,625
  5. Step 5: Solve for x
    x = 390,625/399
  6. Step 6: Final answer
    x = 979.01

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Why These Related Problems?

These problems maintain the same ratio (1.57) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.