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Finding the Fourth Proportional to 660.64, 991.24 and 386.73

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Solution

The fourth proportional to 660.64, 991.24 and 386.73 is: 580.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.64 : 991.24 = 386.73 : x
  2. Step 2: Convert to fraction form
    660.64/991.24 = 386.73/x
  3. Step 3: Cross multiply
    660.64x = 991.24 × 386.73
  4. Step 4: Simplify right side
    660.64x = 383,342.25
  5. Step 5: Solve for x
    x = 383,342.25/660.64
  6. Step 6: Final answer
    x = 580.26

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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.