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Finding the Fourth Proportional to 389.55, 537.68 and 223.78

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Solution

The fourth proportional to 389.55, 537.68 and 223.78 is: 308.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.55 : 537.68 = 223.78 : x
  2. Step 2: Convert to fraction form
    389.55/537.68 = 223.78/x
  3. Step 3: Cross multiply
    389.55x = 537.68 × 223.78
  4. Step 4: Simplify right side
    389.55x = 120,321.25
  5. Step 5: Solve for x
    x = 120,321.25/389.55
  6. Step 6: Final answer
    x = 308.87

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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.