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Finding the Fourth Proportional to 660.23, 989.85 and 221.33

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Solution

The fourth proportional to 660.23, 989.85 and 221.33 is: 331.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.23 : 989.85 = 221.33 : x
  2. Step 2: Convert to fraction form
    660.23/989.85 = 221.33/x
  3. Step 3: Cross multiply
    660.23x = 989.85 × 221.33
  4. Step 4: Simplify right side
    660.23x = 219,086.81
  5. Step 5: Solve for x
    x = 219,086.81/660.23
  6. Step 6: Final answer
    x = 331.83

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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.