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Finding the Fourth Proportional to 139.38, 208.08 and 118.80

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Solution

The fourth proportional to 139.38, 208.08 and 118.80 is: 177.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.38 : 208.08 = 118.80 : x
  2. Step 2: Convert to fraction form
    139.38/208.08 = 118.80/x
  3. Step 3: Cross multiply
    139.38x = 208.08 × 118.80
  4. Step 4: Simplify right side
    139.38x = 24,719.90
  5. Step 5: Solve for x
    x = 24,719.90/139.38
  6. Step 6: Final answer
    x = 177.36

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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.