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Finding the Fourth Proportional to 389.20, 537.32 and 278.96

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Solution

The fourth proportional to 389.20, 537.32 and 278.96 is: 385.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.20 : 537.32 = 278.96 : x
  2. Step 2: Convert to fraction form
    389.20/537.32 = 278.96/x
  3. Step 3: Cross multiply
    389.20x = 537.32 × 278.96
  4. Step 4: Simplify right side
    389.20x = 149,890.79
  5. Step 5: Solve for x
    x = 149,890.79/389.20
  6. Step 6: Final answer
    x = 385.13

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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.