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Finding the Fourth Proportional to 226.80, 312.97 and 128.55

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Solution

The fourth proportional to 226.80, 312.97 and 128.55 is: 177.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    226.80 : 312.97 = 128.55 : x
  2. Step 2: Convert to fraction form
    226.80/312.97 = 128.55/x
  3. Step 3: Cross multiply
    226.80x = 312.97 × 128.55
  4. Step 4: Simplify right side
    226.80x = 40,230.09
  5. Step 5: Solve for x
    x = 40,230.09/226.80
  6. Step 6: Final answer
    x = 177.39

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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.