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Finding the Fourth Proportional to 138.39, 189.85 and 124.39

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Solution

The fourth proportional to 138.39, 189.85 and 124.39 is: 170.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.39 : 189.85 = 124.39 : x
  2. Step 2: Convert to fraction form
    138.39/189.85 = 124.39/x
  3. Step 3: Cross multiply
    138.39x = 189.85 × 124.39
  4. Step 4: Simplify right side
    138.39x = 23,615.44
  5. Step 5: Solve for x
    x = 23,615.44/138.39
  6. Step 6: Final answer
    x = 170.64

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.