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Finding the Fourth Proportional to 660.66, 991.14 and 386.83

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Solution

The fourth proportional to 660.66, 991.14 and 386.83 is: 580.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.66 : 991.14 = 386.83 : x
  2. Step 2: Convert to fraction form
    660.66/991.14 = 386.83/x
  3. Step 3: Cross multiply
    660.66x = 991.14 × 386.83
  4. Step 4: Simplify right side
    660.66x = 383,396.90
  5. Step 5: Solve for x
    x = 383,396.90/660.66
  6. Step 6: Final answer
    x = 580.33

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.