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Finding the Fourth Proportional to 138.69, 191.30 and 127.89

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Solution

The fourth proportional to 138.69, 191.30 and 127.89 is: 176.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.69 : 191.30 = 127.89 : x
  2. Step 2: Convert to fraction form
    138.69/191.30 = 127.89/x
  3. Step 3: Cross multiply
    138.69x = 191.30 × 127.89
  4. Step 4: Simplify right side
    138.69x = 24,464.72
  5. Step 5: Solve for x
    x = 24,464.72/138.69
  6. Step 6: Final answer
    x = 176.40

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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.