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Finding the Fourth Proportional to 660.20, 989.85 and 308.69

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Solution

The fourth proportional to 660.20, 989.85 and 308.69 is: 462.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.20 : 989.85 = 308.69 : x
  2. Step 2: Convert to fraction form
    660.20/989.85 = 308.69/x
  3. Step 3: Cross multiply
    660.20x = 989.85 × 308.69
  4. Step 4: Simplify right side
    660.20x = 305,551.33
  5. Step 5: Solve for x
    x = 305,551.33/660.20
  6. Step 6: Final answer
    x = 462.82

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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.