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Finding the Fourth Proportional to 128.03, 191.97 and 87.39

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Solution

The fourth proportional to 128.03, 191.97 and 87.39 is: 131.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.03 : 191.97 = 87.39 : x
  2. Step 2: Convert to fraction form
    128.03/191.97 = 87.39/x
  3. Step 3: Cross multiply
    128.03x = 191.97 × 87.39
  4. Step 4: Simplify right side
    128.03x = 16,776.26
  5. Step 5: Solve for x
    x = 16,776.26/128.03
  6. Step 6: Final answer
    x = 131.04

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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.