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Finding the Fourth Proportional to 139.77, 191.75 and 138.29

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Solution

The fourth proportional to 139.77, 191.75 and 138.29 is: 189.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.77 : 191.75 = 138.29 : x
  2. Step 2: Convert to fraction form
    139.77/191.75 = 138.29/x
  3. Step 3: Cross multiply
    139.77x = 191.75 × 138.29
  4. Step 4: Simplify right side
    139.77x = 26,515.46
  5. Step 5: Solve for x
    x = 26,515.46/139.77
  6. Step 6: Final answer
    x = 189.71

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.