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Finding the Fourth Proportional to 128.09, 191.22 and 118.98

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Solution

The fourth proportional to 128.09, 191.22 and 118.98 is: 177.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.09 : 191.22 = 118.98 : x
  2. Step 2: Convert to fraction form
    128.09/191.22 = 118.98/x
  3. Step 3: Cross multiply
    128.09x = 191.22 × 118.98
  4. Step 4: Simplify right side
    128.09x = 22,750.91
  5. Step 5: Solve for x
    x = 22,750.91/128.09
  6. Step 6: Final answer
    x = 177.61

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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.