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Finding the Fourth Proportional to 223.38, 308.28 and 128.88

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Solution

The fourth proportional to 223.38, 308.28 and 128.88 is: 177.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    223.38 : 308.28 = 128.88 : x
  2. Step 2: Convert to fraction form
    223.38/308.28 = 128.88/x
  3. Step 3: Cross multiply
    223.38x = 308.28 × 128.88
  4. Step 4: Simplify right side
    223.38x = 39,731.13
  5. Step 5: Solve for x
    x = 39,731.13/223.38
  6. Step 6: Final answer
    x = 177.86

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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.