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Finding the Fourth Proportional to 660.20, 910.85 and 439.28

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Solution

The fourth proportional to 660.20, 910.85 and 439.28 is: 606.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.20 : 910.85 = 439.28 : x
  2. Step 2: Convert to fraction form
    660.20/910.85 = 439.28/x
  3. Step 3: Cross multiply
    660.20x = 910.85 × 439.28
  4. Step 4: Simplify right side
    660.20x = 400,118.27
  5. Step 5: Solve for x
    x = 400,118.27/660.20
  6. Step 6: Final answer
    x = 606.06

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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.