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Finding the Fourth Proportional to 406.82, 609.09 and 221.05

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Solution

The fourth proportional to 406.82, 609.09 and 221.05 is: 330.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    406.82 : 609.09 = 221.05 : x
  2. Step 2: Convert to fraction form
    406.82/609.09 = 221.05/x
  3. Step 3: Cross multiply
    406.82x = 609.09 × 221.05
  4. Step 4: Simplify right side
    406.82x = 134,639.34
  5. Step 5: Solve for x
    x = 134,639.34/406.82
  6. Step 6: Final answer
    x = 330.96

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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.