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Finding the Third Proportional to 251.30 and 399.80

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Solution

The third proportional to 251.30 and 399.80 is: 636.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    251.30 : 399.80 = 399.80 : x
  2. Step 2: Convert to fraction form
    251.30/399.80 = 399.80/x
  3. Step 3: Cross multiply
    251.30x = 399.80 × 399.80
  4. Step 4: Simplify right side
    251.30x = 159,837.54
  5. Step 5: Solve for x
    x = 159,837.54/251.30
  6. Step 6: Final answer
    x = 636.05

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Why These Related Problems?

These problems maintain the same ratio (1.59) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.