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Finding the Fourth Proportional to 311.72, 430.18 and 180.74

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Solution

The fourth proportional to 311.72, 430.18 and 180.74 is: 249.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.72 : 430.18 = 180.74 : x
  2. Step 2: Convert to fraction form
    311.72/430.18 = 180.74/x
  3. Step 3: Cross multiply
    311.72x = 430.18 × 180.74
  4. Step 4: Simplify right side
    311.72x = 77,750.73
  5. Step 5: Solve for x
    x = 77,750.73/311.72
  6. Step 6: Final answer
    x = 249.42

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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.