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Finding the Fourth Proportional to 101.17, 138.92 and 88.71

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Solution

The fourth proportional to 101.17, 138.92 and 88.71 is: 121.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.17 : 138.92 = 88.71 : x
  2. Step 2: Convert to fraction form
    101.17/138.92 = 88.71/x
  3. Step 3: Cross multiply
    101.17x = 138.92 × 88.71
  4. Step 4: Simplify right side
    101.17x = 12,323.59
  5. Step 5: Solve for x
    x = 12,323.59/101.17
  6. Step 6: Final answer
    x = 121.81

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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.