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Finding the Fourth Proportional to 139.78, 208.08 and 133.14

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Solution

The fourth proportional to 139.78, 208.08 and 133.14 is: 198.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.78 : 208.08 = 133.14 : x
  2. Step 2: Convert to fraction form
    139.78/208.08 = 133.14/x
  3. Step 3: Cross multiply
    139.78x = 208.08 × 133.14
  4. Step 4: Simplify right side
    139.78x = 27,704.18
  5. Step 5: Solve for x
    x = 27,704.18/139.78
  6. Step 6: Final answer
    x = 198.20

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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.