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Finding the Fourth Proportional to 660.66, 911.86 and 398.82

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Solution

The fourth proportional to 660.66, 911.86 and 398.82 is: 550.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.66 : 911.86 = 398.82 : x
  2. Step 2: Convert to fraction form
    660.66/911.86 = 398.82/x
  3. Step 3: Cross multiply
    660.66x = 911.86 × 398.82
  4. Step 4: Simplify right side
    660.66x = 363,670.43
  5. Step 5: Solve for x
    x = 363,670.43/660.66
  6. Step 6: Final answer
    x = 550.47

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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.