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Finding the Fourth Proportional to 203.19, 280.28 and 128.55

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Solution

The fourth proportional to 203.19, 280.28 and 128.55 is: 177.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    203.19 : 280.28 = 128.55 : x
  2. Step 2: Convert to fraction form
    203.19/280.28 = 128.55/x
  3. Step 3: Cross multiply
    203.19x = 280.28 × 128.55
  4. Step 4: Simplify right side
    203.19x = 36,029.35
  5. Step 5: Solve for x
    x = 36,029.35/203.19
  6. Step 6: Final answer
    x = 177.32

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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.