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Finding the Fourth Proportional to 660.30, 911.28 and 439.17

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Solution

The fourth proportional to 660.30, 911.28 and 439.17 is: 606.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.30 : 911.28 = 439.17 : x
  2. Step 2: Convert to fraction form
    660.30/911.28 = 439.17/x
  3. Step 3: Cross multiply
    660.30x = 911.28 × 439.17
  4. Step 4: Simplify right side
    660.30x = 400,206.84
  5. Step 5: Solve for x
    x = 400,206.84/660.30
  6. Step 6: Final answer
    x = 606.10

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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.