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Finding the Fourth Proportional to 215.78, 299.85 and 213.56

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Solution

The fourth proportional to 215.78, 299.85 and 213.56 is: 296.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    215.78 : 299.85 = 213.56 : x
  2. Step 2: Convert to fraction form
    215.78/299.85 = 213.56/x
  3. Step 3: Cross multiply
    215.78x = 299.85 × 213.56
  4. Step 4: Simplify right side
    215.78x = 64,034.90
  5. Step 5: Solve for x
    x = 64,034.90/215.78
  6. Step 6: Final answer
    x = 296.76

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.