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Finding the Fourth Proportional to 660.39, 911.49 and 411.66

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Solution

The fourth proportional to 660.39, 911.49 and 411.66 is: 568.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.39 : 911.49 = 411.66 : x
  2. Step 2: Convert to fraction form
    660.39/911.49 = 411.66/x
  3. Step 3: Cross multiply
    660.39x = 911.49 × 411.66
  4. Step 4: Simplify right side
    660.39x = 375,228.74
  5. Step 5: Solve for x
    x = 375,228.74/660.39
  6. Step 6: Final answer
    x = 568.19

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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.