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Finding the Fourth Proportional to 139.41, 193.41 and 138.20

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Solution

The fourth proportional to 139.41, 193.41 and 138.20 is: 191.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.41 : 193.41 = 138.20 : x
  2. Step 2: Convert to fraction form
    139.41/193.41 = 138.20/x
  3. Step 3: Cross multiply
    139.41x = 193.41 × 138.20
  4. Step 4: Simplify right side
    139.41x = 26,728.29
  5. Step 5: Solve for x
    x = 26,728.29/139.41
  6. Step 6: Final answer
    x = 191.72

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.