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Finding the Fourth Proportional to 389.39, 584.12 and 145.91

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Solution

The fourth proportional to 389.39, 584.12 and 145.91 is: 218.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.39 : 584.12 = 145.91 : x
  2. Step 2: Convert to fraction form
    389.39/584.12 = 145.91/x
  3. Step 3: Cross multiply
    389.39x = 584.12 × 145.91
  4. Step 4: Simplify right side
    389.39x = 85,225.30
  5. Step 5: Solve for x
    x = 85,225.30/389.39
  6. Step 6: Final answer
    x = 218.87

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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.