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Finding the Fourth Proportional to 354.55, 489.23 and 221.80

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Solution

The fourth proportional to 354.55, 489.23 and 221.80 is: 306.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    354.55 : 489.23 = 221.80 : x
  2. Step 2: Convert to fraction form
    354.55/489.23 = 221.80/x
  3. Step 3: Cross multiply
    354.55x = 489.23 × 221.80
  4. Step 4: Simplify right side
    354.55x = 108,511.21
  5. Step 5: Solve for x
    x = 108,511.21/354.55
  6. Step 6: Final answer
    x = 306.05

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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.