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Finding the Fourth Proportional to 207.09, 309.83 and 138.03

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Solution

The fourth proportional to 207.09, 309.83 and 138.03 is: 206.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    207.09 : 309.83 = 138.03 : x
  2. Step 2: Convert to fraction form
    207.09/309.83 = 138.03/x
  3. Step 3: Cross multiply
    207.09x = 309.83 × 138.03
  4. Step 4: Simplify right side
    207.09x = 42,765.14
  5. Step 5: Solve for x
    x = 42,765.14/207.09
  6. Step 6: Final answer
    x = 206.51

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.