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Finding the Fourth Proportional to 138.80, 207.24 and 137.79

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Solution

The fourth proportional to 138.80, 207.24 and 137.79 is: 205.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.80 : 207.24 = 137.79 : x
  2. Step 2: Convert to fraction form
    138.80/207.24 = 137.79/x
  3. Step 3: Cross multiply
    138.80x = 207.24 × 137.79
  4. Step 4: Simplify right side
    138.80x = 28,555.60
  5. Step 5: Solve for x
    x = 28,555.60/138.80
  6. Step 6: Final answer
    x = 205.74

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.