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Finding the Fourth Proportional to 660.21, 911.12 and 411.68

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Solution

The fourth proportional to 660.21, 911.12 and 411.68 is: 568.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.21 : 911.12 = 411.68 : x
  2. Step 2: Convert to fraction form
    660.21/911.12 = 411.68/x
  3. Step 3: Cross multiply
    660.21x = 911.12 × 411.68
  4. Step 4: Simplify right side
    660.21x = 375,083.27
  5. Step 5: Solve for x
    x = 375,083.27/660.21
  6. Step 6: Final answer
    x = 568.13

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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.