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Finding the Fourth Proportional to 128.94, 193.08 and 68.09

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Solution

The fourth proportional to 128.94, 193.08 and 68.09 is: 101.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.94 : 193.08 = 68.09 : x
  2. Step 2: Convert to fraction form
    128.94/193.08 = 68.09/x
  3. Step 3: Cross multiply
    128.94x = 193.08 × 68.09
  4. Step 4: Simplify right side
    128.94x = 13,147.19
  5. Step 5: Solve for x
    x = 13,147.19/128.94
  6. Step 6: Final answer
    x = 101.96

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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.