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Finding the Fourth Proportional to 221.80, 330.73 and 206.90

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Solution

The fourth proportional to 221.80, 330.73 and 206.90 is: 308.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.80 : 330.73 = 206.90 : x
  2. Step 2: Convert to fraction form
    221.80/330.73 = 206.90/x
  3. Step 3: Cross multiply
    221.80x = 330.73 × 206.90
  4. Step 4: Simplify right side
    221.80x = 68,428.04
  5. Step 5: Solve for x
    x = 68,428.04/221.80
  6. Step 6: Final answer
    x = 308.51

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.