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Finding the Fourth Proportional to 660.27, 911.40 and 408.39

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Solution

The fourth proportional to 660.27, 911.40 and 408.39 is: 563.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.27 : 911.40 = 408.39 : x
  2. Step 2: Convert to fraction form
    660.27/911.40 = 408.39/x
  3. Step 3: Cross multiply
    660.27x = 911.40 × 408.39
  4. Step 4: Simplify right side
    660.27x = 372,200.71
  5. Step 5: Solve for x
    x = 372,200.71/660.27
  6. Step 6: Final answer
    x = 563.71

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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.