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Finding the Fourth Proportional to 388.40, 581.99 and 205.61

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Solution

The fourth proportional to 388.40, 581.99 and 205.61 is: 308.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.40 : 581.99 = 205.61 : x
  2. Step 2: Convert to fraction form
    388.40/581.99 = 205.61/x
  3. Step 3: Cross multiply
    388.40x = 581.99 × 205.61
  4. Step 4: Simplify right side
    388.40x = 119,659.03
  5. Step 5: Solve for x
    x = 119,659.03/388.40
  6. Step 6: Final answer
    x = 308.09

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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.