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Finding the Fourth Proportional to 660.50, 911.49 and 398.58

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Solution

The fourth proportional to 660.50, 911.49 and 398.58 is: 550.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.50 : 911.49 = 398.58 : x
  2. Step 2: Convert to fraction form
    660.50/911.49 = 398.58/x
  3. Step 3: Cross multiply
    660.50x = 911.49 × 398.58
  4. Step 4: Simplify right side
    660.50x = 363,301.68
  5. Step 5: Solve for x
    x = 363,301.68/660.50
  6. Step 6: Final answer
    x = 550.04

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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.