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Finding the Fourth Proportional to 135.30, 203.78 and 128.82

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Solution

The fourth proportional to 135.30, 203.78 and 128.82 is: 194.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    135.30 : 203.78 = 128.82 : x
  2. Step 2: Convert to fraction form
    135.30/203.78 = 128.82/x
  3. Step 3: Cross multiply
    135.30x = 203.78 × 128.82
  4. Step 4: Simplify right side
    135.30x = 26,250.01
  5. Step 5: Solve for x
    x = 26,250.01/135.30
  6. Step 6: Final answer
    x = 194.02

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.