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Finding the Fourth Proportional to 128.82, 191.88 and 127.25

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Solution

The fourth proportional to 128.82, 191.88 and 127.25 is: 189.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.82 : 191.88 = 127.25 : x
  2. Step 2: Convert to fraction form
    128.82/191.88 = 127.25/x
  3. Step 3: Cross multiply
    128.82x = 191.88 × 127.25
  4. Step 4: Simplify right side
    128.82x = 24,416.73
  5. Step 5: Solve for x
    x = 24,416.73/128.82
  6. Step 6: Final answer
    x = 189.54

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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.