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Finding the Fourth Proportional to 389.90, 585.02 and 207.08

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Solution

The fourth proportional to 389.90, 585.02 and 207.08 is: 310.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.90 : 585.02 = 207.08 : x
  2. Step 2: Convert to fraction form
    389.90/585.02 = 207.08/x
  3. Step 3: Cross multiply
    389.90x = 585.02 × 207.08
  4. Step 4: Simplify right side
    389.90x = 121,147.37
  5. Step 5: Solve for x
    x = 121,147.37/389.90
  6. Step 6: Final answer
    x = 310.71

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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.