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Finding the Fourth Proportional to 538.39, 807.86 and 213.99

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Solution

The fourth proportional to 538.39, 807.86 and 213.99 is: 321.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.39 : 807.86 = 213.99 : x
  2. Step 2: Convert to fraction form
    538.39/807.86 = 213.99/x
  3. Step 3: Cross multiply
    538.39x = 807.86 × 213.99
  4. Step 4: Simplify right side
    538.39x = 172,873.96
  5. Step 5: Solve for x
    x = 172,873.96/538.39
  6. Step 6: Final answer
    x = 321.09

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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.