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Finding the Fourth Proportional to 660.57, 911.40 and 411.90

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Solution

The fourth proportional to 660.57, 911.40 and 411.90 is: 568.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.57 : 911.40 = 411.90 : x
  2. Step 2: Convert to fraction form
    660.57/911.40 = 411.90/x
  3. Step 3: Cross multiply
    660.57x = 911.40 × 411.90
  4. Step 4: Simplify right side
    660.57x = 375,405.66
  5. Step 5: Solve for x
    x = 375,405.66/660.57
  6. Step 6: Final answer
    x = 568.31

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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.