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Finding the Fourth Proportional to 389.21, 537.12 and 231.80

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Solution

The fourth proportional to 389.21, 537.12 and 231.80 is: 319.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.21 : 537.12 = 231.80 : x
  2. Step 2: Convert to fraction form
    389.21/537.12 = 231.80/x
  3. Step 3: Cross multiply
    389.21x = 537.12 × 231.80
  4. Step 4: Simplify right side
    389.21x = 124,501.73
  5. Step 5: Solve for x
    x = 124,501.73/389.21
  6. Step 6: Final answer
    x = 319.89

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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.