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Finding the Fourth Proportional to 287.85, 396.60 and 203.79

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Solution

The fourth proportional to 287.85, 396.60 and 203.79 is: 280.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.85 : 396.60 = 203.79 : x
  2. Step 2: Convert to fraction form
    287.85/396.60 = 203.79/x
  3. Step 3: Cross multiply
    287.85x = 396.60 × 203.79
  4. Step 4: Simplify right side
    287.85x = 80,823.11
  5. Step 5: Solve for x
    x = 80,823.11/287.85
  6. Step 6: Final answer
    x = 280.78

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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.