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Finding the Fourth Proportional to 139.80, 208.24 and 132.78

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Solution

The fourth proportional to 139.80, 208.24 and 132.78 is: 197.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.80 : 208.24 = 132.78 : x
  2. Step 2: Convert to fraction form
    139.80/208.24 = 132.78/x
  3. Step 3: Cross multiply
    139.80x = 208.24 × 132.78
  4. Step 4: Simplify right side
    139.80x = 27,650.11
  5. Step 5: Solve for x
    x = 27,650.11/139.80
  6. Step 6: Final answer
    x = 197.78

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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.