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Finding the Third Proportional to 390.25 and 824

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Solution

The third proportional to 390.25 and 824 is: 1,739.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.25 : 824 = 824 : x
  2. Step 2: Convert to fraction form
    390.25/824 = 824/x
  3. Step 3: Cross multiply
    390.25x = 824 × 824
  4. Step 4: Simplify right side
    390.25x = 678,976
  5. Step 5: Solve for x
    x = 678,976/390.25
  6. Step 6: Final answer
    x = 1,739.85

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Why These Related Problems?

These problems maintain the same ratio (2.11) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.