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Finding the Fourth Proportional to 138.90, 190.40 and 137.96

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Solution

The fourth proportional to 138.90, 190.40 and 137.96 is: 189.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.90 : 190.40 = 137.96 : x
  2. Step 2: Convert to fraction form
    138.90/190.40 = 137.96/x
  3. Step 3: Cross multiply
    138.90x = 190.40 × 137.96
  4. Step 4: Simplify right side
    138.90x = 26,267.58
  5. Step 5: Solve for x
    x = 26,267.58/138.90
  6. Step 6: Final answer
    x = 189.11

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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.