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Finding the Fourth Proportional to 89.03, 133.07 and 81.28

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Solution

The fourth proportional to 89.03, 133.07 and 81.28 is: 121.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    89.03 : 133.07 = 81.28 : x
  2. Step 2: Convert to fraction form
    89.03/133.07 = 81.28/x
  3. Step 3: Cross multiply
    89.03x = 133.07 × 81.28
  4. Step 4: Simplify right side
    89.03x = 10,815.93
  5. Step 5: Solve for x
    x = 10,815.93/89.03
  6. Step 6: Final answer
    x = 121.49

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.