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Finding the Fourth Proportional to 138.09, 190.41 and 88.18

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Solution

The fourth proportional to 138.09, 190.41 and 88.18 is: 121.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.09 : 190.41 = 88.18 : x
  2. Step 2: Convert to fraction form
    138.09/190.41 = 88.18/x
  3. Step 3: Cross multiply
    138.09x = 190.41 × 88.18
  4. Step 4: Simplify right side
    138.09x = 16,790.35
  5. Step 5: Solve for x
    x = 16,790.35/138.09
  6. Step 6: Final answer
    x = 121.59

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.