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Finding the Fourth Proportional to 139.48, 207.89 and 138.34

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Solution

The fourth proportional to 139.48, 207.89 and 138.34 is: 206.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.48 : 207.89 = 138.34 : x
  2. Step 2: Convert to fraction form
    139.48/207.89 = 138.34/x
  3. Step 3: Cross multiply
    139.48x = 207.89 × 138.34
  4. Step 4: Simplify right side
    139.48x = 28,759.50
  5. Step 5: Solve for x
    x = 28,759.50/139.48
  6. Step 6: Final answer
    x = 206.19

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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.