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Finding the Fourth Proportional to 138.70, 191.55 and 114.31

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Solution

The fourth proportional to 138.70, 191.55 and 114.31 is: 157.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.70 : 191.55 = 114.31 : x
  2. Step 2: Convert to fraction form
    138.70/191.55 = 114.31/x
  3. Step 3: Cross multiply
    138.70x = 191.55 × 114.31
  4. Step 4: Simplify right side
    138.70x = 21,896.08
  5. Step 5: Solve for x
    x = 21,896.08/138.70
  6. Step 6: Final answer
    x = 157.87

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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.