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Finding the Fourth Proportional to 227.05, 313.19 and 128.78

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Solution

The fourth proportional to 227.05, 313.19 and 128.78 is: 177.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    227.05 : 313.19 = 128.78 : x
  2. Step 2: Convert to fraction form
    227.05/313.19 = 128.78/x
  3. Step 3: Cross multiply
    227.05x = 313.19 × 128.78
  4. Step 4: Simplify right side
    227.05x = 40,332.75
  5. Step 5: Solve for x
    x = 40,332.75/227.05
  6. Step 6: Final answer
    x = 177.64

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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.