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Finding the Fourth Proportional to 287.55, 396.23 and 221.85

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Solution

The fourth proportional to 287.55, 396.23 and 221.85 is: 305.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.55 : 396.23 = 221.85 : x
  2. Step 2: Convert to fraction form
    287.55/396.23 = 221.85/x
  3. Step 3: Cross multiply
    287.55x = 396.23 × 221.85
  4. Step 4: Simplify right side
    287.55x = 87,902.52
  5. Step 5: Solve for x
    x = 87,902.52/287.55
  6. Step 6: Final answer
    x = 305.69

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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.