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Finding the Fourth Proportional to 154.39, 213.03 and 85.39

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Solution

The fourth proportional to 154.39, 213.03 and 85.39 is: 117.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    154.39 : 213.03 = 85.39 : x
  2. Step 2: Convert to fraction form
    154.39/213.03 = 85.39/x
  3. Step 3: Cross multiply
    154.39x = 213.03 × 85.39
  4. Step 4: Simplify right side
    154.39x = 18,190.63
  5. Step 5: Solve for x
    x = 18,190.63/154.39
  6. Step 6: Final answer
    x = 117.82

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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.