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Finding the Fourth Proportional to 135.39, 203.09 and 39.20

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Solution

The fourth proportional to 135.39, 203.09 and 39.20 is: 58.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    135.39 : 203.09 = 39.20 : x
  2. Step 2: Convert to fraction form
    135.39/203.09 = 39.20/x
  3. Step 3: Cross multiply
    135.39x = 203.09 × 39.20
  4. Step 4: Simplify right side
    135.39x = 7,961.13
  5. Step 5: Solve for x
    x = 7,961.13/135.39
  6. Step 6: Final answer
    x = 58.80

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.