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Finding the Fourth Proportional to 538.21, 807.43 and 213.57

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Solution

The fourth proportional to 538.21, 807.43 and 213.57 is: 320.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.21 : 807.43 = 213.57 : x
  2. Step 2: Convert to fraction form
    538.21/807.43 = 213.57/x
  3. Step 3: Cross multiply
    538.21x = 807.43 × 213.57
  4. Step 4: Simplify right side
    538.21x = 172,437.72
  5. Step 5: Solve for x
    x = 172,437.72/538.21
  6. Step 6: Final answer
    x = 320.39

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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.