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Finding the Fourth Proportional to 221.65, 330.49 and 217.55

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Solution

The fourth proportional to 221.65, 330.49 and 217.55 is: 324.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.65 : 330.49 = 217.55 : x
  2. Step 2: Convert to fraction form
    221.65/330.49 = 217.55/x
  3. Step 3: Cross multiply
    221.65x = 330.49 × 217.55
  4. Step 4: Simplify right side
    221.65x = 71,899.20
  5. Step 5: Solve for x
    x = 71,899.20/221.65
  6. Step 6: Final answer
    x = 324.39

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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.