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Finding the Third Proportional to 307.13 and 399.09

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Solution

The third proportional to 307.13 and 399.09 is: 518.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    307.13 : 399.09 = 399.09 : x
  2. Step 2: Convert to fraction form
    307.13/399.09 = 399.09/x
  3. Step 3: Cross multiply
    307.13x = 399.09 × 399.09
  4. Step 4: Simplify right side
    307.13x = 159,275.82
  5. Step 5: Solve for x
    x = 159,275.82/307.13
  6. Step 6: Final answer
    x = 518.60

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Why These Related Problems?

These problems maintain the same ratio (1.30) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.