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Finding the Fourth Proportional to 139.41, 208.80 and 136.64

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Solution

The fourth proportional to 139.41, 208.80 and 136.64 is: 204.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.41 : 208.80 = 136.64 : x
  2. Step 2: Convert to fraction form
    139.41/208.80 = 136.64/x
  3. Step 3: Cross multiply
    139.41x = 208.80 × 136.64
  4. Step 4: Simplify right side
    139.41x = 28,530.25
  5. Step 5: Solve for x
    x = 28,530.25/139.41
  6. Step 6: Final answer
    x = 204.66

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.