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Finding the Fourth Proportional to 128.97, 192.08 and 128.29

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Solution

The fourth proportional to 128.97, 192.08 and 128.29 is: 191.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.97 : 192.08 = 128.29 : x
  2. Step 2: Convert to fraction form
    128.97/192.08 = 128.29/x
  3. Step 3: Cross multiply
    128.97x = 192.08 × 128.29
  4. Step 4: Simplify right side
    128.97x = 24,641.94
  5. Step 5: Solve for x
    x = 24,641.94/128.97
  6. Step 6: Final answer
    x = 191.07

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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.