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Finding the Fourth Proportional to 221.05, 331.64 and 129.58

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Solution

The fourth proportional to 221.05, 331.64 and 129.58 is: 194.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.05 : 331.64 = 129.58 : x
  2. Step 2: Convert to fraction form
    221.05/331.64 = 129.58/x
  3. Step 3: Cross multiply
    221.05x = 331.64 × 129.58
  4. Step 4: Simplify right side
    221.05x = 42,973.91
  5. Step 5: Solve for x
    x = 42,973.91/221.05
  6. Step 6: Final answer
    x = 194.41

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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.