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Finding the Fourth Proportional to 871.23, 1,306.83 and 213.11

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Solution

The fourth proportional to 871.23, 1,306.83 and 213.11 is: 319.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    871.23 : 1,306.83 = 213.11 : x
  2. Step 2: Convert to fraction form
    871.23/1,306.83 = 213.11/x
  3. Step 3: Cross multiply
    871.23x = 1,306.83 × 213.11
  4. Step 4: Simplify right side
    871.23x = 278,498.54
  5. Step 5: Solve for x
    x = 278,498.54/871.23
  6. Step 6: Final answer
    x = 319.66

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.