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Finding the Fourth Proportional to 311.20, 429.54 and 211.57

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Solution

The fourth proportional to 311.20, 429.54 and 211.57 is: 292.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.20 : 429.54 = 211.57 : x
  2. Step 2: Convert to fraction form
    311.20/429.54 = 211.57/x
  3. Step 3: Cross multiply
    311.20x = 429.54 × 211.57
  4. Step 4: Simplify right side
    311.20x = 90,877.78
  5. Step 5: Solve for x
    x = 90,877.78/311.20
  6. Step 6: Final answer
    x = 292.02

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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.