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Finding the Fourth Proportional to 660.90, 911.98 and 395.29

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Solution

The fourth proportional to 660.90, 911.98 and 395.29 is: 545.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.90 : 911.98 = 395.29 : x
  2. Step 2: Convert to fraction form
    660.90/911.98 = 395.29/x
  3. Step 3: Cross multiply
    660.90x = 911.98 × 395.29
  4. Step 4: Simplify right side
    660.90x = 360,496.57
  5. Step 5: Solve for x
    x = 360,496.57/660.90
  6. Step 6: Final answer
    x = 545.46

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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.