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Finding the Fourth Proportional to 128.94, 177.81 and 97.85

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Solution

The fourth proportional to 128.94, 177.81 and 97.85 is: 134.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.94 : 177.81 = 97.85 : x
  2. Step 2: Convert to fraction form
    128.94/177.81 = 97.85/x
  3. Step 3: Cross multiply
    128.94x = 177.81 × 97.85
  4. Step 4: Simplify right side
    128.94x = 17,397.67
  5. Step 5: Solve for x
    x = 17,397.67/128.94
  6. Step 6: Final answer
    x = 134.93

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.