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Finding the Fourth Proportional to 128.87, 193.20 and 88.37

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Solution

The fourth proportional to 128.87, 193.20 and 88.37 is: 132.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.87 : 193.20 = 88.37 : x
  2. Step 2: Convert to fraction form
    128.87/193.20 = 88.37/x
  3. Step 3: Cross multiply
    128.87x = 193.20 × 88.37
  4. Step 4: Simplify right side
    128.87x = 17,073.08
  5. Step 5: Solve for x
    x = 17,073.08/128.87
  6. Step 6: Final answer
    x = 132.48

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.