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Finding the Fourth Proportional to 389.90, 585.14 and 243.87

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Solution

The fourth proportional to 389.90, 585.14 and 243.87 is: 365.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.90 : 585.14 = 243.87 : x
  2. Step 2: Convert to fraction form
    389.90/585.14 = 243.87/x
  3. Step 3: Cross multiply
    389.90x = 585.14 × 243.87
  4. Step 4: Simplify right side
    389.90x = 142,695.17
  5. Step 5: Solve for x
    x = 142,695.17/389.90
  6. Step 6: Final answer
    x = 365.98

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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.